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5556 questions

Question 5541Question

The following passage is adapted from an essay on nineteenth-century optics and astronomy:

In the spring of 1800, the astronomer William Herschel conducted a series of experiments to measure the thermal energy associated with different colors of the visible solar spectrum. Passing sunlight through a glass prism, he projected the resulting rainbow spectrum onto a flat surface and placed sensitive glass-bulb thermometers within each colored band—violet, blue, green, yellow, orange, and red. To ensure that room temperature changes did not skew his measurements, Herschel positioned additional control thermometers in the shade near the spectrum table, away from the direct sunlight.

During his measurements, Herschel noticed a systematic increase in recorded temperature from the violet end toward the red end of the spectrum. Red light consistently registered a significantly higher temperature than green or violet light. Intrigued by this thermal progression, Herschel decided to measure the temperature just beyond the red edge of the visible spectrum, where no visible illumination was apparent. To his surprise, this dark region beyond the red boundary registered the highest temperature of all, proving the existence of invisible rays carrying heat energy—what Herschel initially termed "calorific rays" and what scientists later renamed infrared radiation.

In his papers presented to the Royal Society of London, Herschel carefully described his experimental apparatus. He mounted a glass prism on an adjustable stand positioned near a small opening in a window shutter, allowing a narrow beam of sunlight to enter the darkened room. The target surface holding the test thermometers was covered with thick white paper to render the boundaries of the spectral colors sharply visible. Herschel stressed that the shade-stationed control thermometers were crucial for verifying that ambient room air fluctuations were separate from the heat generated by the isolated light rays.

Based on the passage, where did Herschel place the control thermometers during his experiment?

Show answer & explanation

Answer: In the shade near the table holding the spectrum

Answer

In the shade near the table holding the spectrum
The correct answer accurately restates the explicit detail given in the passage, which mentions that Herschel placed the control thermometers in the shade near the spectrum table to monitor ambient room temperature.

Step-by-Step Solution

1
Locate the keywords 'control thermometers' in the passage text.
Found in Paragraph 1: 'Herschel positioned additional control thermometers in the shade near the spectrum table, away from the direct sunlight.'
Explicit detail questions require finding the exact sentence where the specific term is discussed.
2
Match the location described in the passage to the correct option.
The text explicitly specifies that the control thermometers were placed in the shade near the table.
Literal comprehension relies directly on stated facts rather than inferences.

Key Concept

Identifying Explicit Details in a Text
Estimated Time:1m 0s
Question 5542Question

A pharmaceutical laboratory formulates a liquid medication by combining Active Ingredient X, Stabilizer Y, and Purified Water in a ratio of 3:4:83 : 4 : 8 by volume. A technician needs to prepare a batch of this medication that contains exactly 360 mL360\text{ mL} of Stabilizer Y. How many total milliliters of liquid medication will this batch contain?

Show answer & explanation

Answer: 1,350 mL1,350\text{ mL}

Answer

1,350 mL1,350\text{ mL}
To find the total batch volume, determine the value of one part in the ratio. The three components (Active Ingredient X, Stabilizer Y, and Purified Water) are mixed in a ratio of 3:4:83 : 4 : 8, giving a total of 3+4+8=153 + 4 + 8 = 15 parts. Stabilizer Y represents 44 of these parts and has a volume of 360 mL360\text{ mL}. Dividing 360360 by 44 gives 90 mL90\text{ mL} per part. Multiplying 90 mL90\text{ mL} by the total 1515 parts yields 1,350 mL1,350\text{ mL}.

Step-by-Step Solution

1
Find the total number of parts in the ratio.
Total parts = 3+4+8=153 + 4 + 8 = 15 parts.
The complete mixture is made up of the sum of the ratio components.
2
Determine the volume represented by a single ratio part.
Value of 11 part = 360 mL4=90 mL\frac{360\text{ mL}}{4} = 90\text{ mL}.
Stabilizer Y accounts for 44 parts of the total ratio and has a volume of 360 mL360\text{ mL}.
3
Calculate the total volume of the batch.
Total volume = 15×90 mL=1,350 mL15 \times 90\text{ mL} = 1,350\text{ mL}.
Multiply the single-part volume by the total number of parts.

Key Concept

Solving Part-to-Total Proportions with Multiple Components
Estimated Time:1m 15s
Question 5543Question

An automated agricultural sprinkler sweeps across a section of a circular field, forming a circular sector. The area of the irrigated sector is 45π45\pi square meters, and the length of the outer boundary arc of the sector is 6π6\pi meters. What is the radius, in meters, of the circular field?

Show answer & explanation

Answer: 15

Answer

15 meters
Using the relationship between sector area, arc length, and radius, A=12rsA = \frac{1}{2} r s, we substitute A=45πA = 45\pi and s=6πs = 6\pi to get 45π=12r(6π)=3πr45\pi = \frac{1}{2} r (6\pi) = 3\pi r. Solving for rr gives r=15r = 15 meters.

Step-by-Step Solution

1
Recall the formulas for sector area (AA) and arc length (ss) in terms of radius (rr) and central angle (θ\theta in radians).
s=rθs = r\theta and A=12r2θA = \frac{1}{2}r^2\theta
These are the fundamental geometric formulas for circular sectors.
2
Express the sector area formula in terms of arc length ss.
A=12r(rθ)=12rsA = \frac{1}{2} r (r\theta) = \frac{1}{2} r s
Substituting s=rθs = r\theta simplifies the calculation by eliminating the central angle θ\theta.
3
Substitute the given values A=45πA = 45\pi and s=6πs = 6\pi into the simplified formula and solve for rr.
45π=12r(6π)    45π=3πr    r=1545\pi = \frac{1}{2} r (6\pi) \implies 45\pi = 3\pi r \implies r = 15
Dividing both sides by 3π3\pi yields the radius r=15r = 15 meters.

Key Concept

Relationship between Sector Area, Arc Length, and Radius
Question 5544Question

In the standard (x,y)(x, y) coordinate plane, a circle is defined by the equation x2+y2+14x6y+9=0x^2 + y^2 + 14x - 6y + 9 = 0. What is the area, in square units, of the region enclosed by the circle?

Show answer & explanation

Answer: 49π49\pi

Answer

The area of the region enclosed by the circle is 49π49\pi square units.
To find the area of the circle, we rewrite the equation x2+y2+14x6y+9=0x^2 + y^2 + 14x - 6y + 9 = 0 in standard form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2. Regrouping gives (x2+14x)+(y26y)=9(x^2 + 14x) + (y^2 - 6y) = -9. Completing the square for xx requires adding (142)2=49(\frac{14}{2})^2 = 49, and for yy requires adding (62)2=9(\frac{-6}{2})^2 = 9. Adding both to the right side gives 9+49+9=49-9 + 49 + 9 = 49. Thus, the standard equation is (x+7)2+(y3)2=49(x + 7)^2 + (y - 3)^2 = 49, yielding r2=49r^2 = 49. The area enclosed by the circle is πr2=49π\pi r^2 = 49\pi.

Step-by-Step Solution

1
Group terms and move the constant term to the right side of the equation.
(x2+14x)+(y26y)=9(x^2 + 14x) + (y^2 - 6y) = -9
Grouping xx-terms and yy-terms prepares the equation for completing the square.
2
Complete the square for both xx and yy expressions by adding (142)2=49(\frac{14}{2})^2 = 49 and (62)2=9(\frac{-6}{2})^2 = 9 to both sides.
(x2+14x+49)+(y26y+9)=9+49+9(x^2 + 14x + 49) + (y^2 - 6y + 9) = -9 + 49 + 9
Adding these values turns the quadratic expressions into perfect square trinomials while keeping the equation balanced.
3
Write in standard circle equation form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2 to identify r2r^2.
(x+7)2+(y3)2=49(x + 7)^2 + (y - 3)^2 = 49, so r2=49r^2 = 49
The standard form directly gives the radius squared, r2=49r^2 = 49.
4
Calculate the area of the circle using the formula A=πr2A = \pi r^2.
A=π(49)=49πA = \pi (49) = 49\pi
Substituting r2=49r^2 = 49 into the area formula gives the final enclosed area.

Key Concept

Converting general circle equation x2+y2+Dx+Ey+F=0x^2 + y^2 + Dx + Ey + F = 0 to standard form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2 by completing the square.
Question 5545Question

A quality control laboratory tested four battery models to measure the proportion of initial charge retained after 24 hours of continuous operation. The recorded results for each model are listed below:

- Model Alpha: 1320\frac{13}{20}
- Model Beta: 64.5%64.5\%
- Model Gamma: 58\frac{5}{8}
- Model Delta: 0.6380.638

Which of the following represents the battery models arranged in order from least to greatest proportion of remaining charge?

Drag items to arrange them in the correct order

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Answer

The correct order from least to greatest proportion of remaining charge is Model Gamma (58\frac{5}{8}), Model Delta (0.6380.638), Model Beta (64.5%64.5\%), and Model Alpha (1320\frac{13}{20}).
Converting each model's retained charge to decimal form gives Model Gamma =58=0.625= \frac{5}{8} = 0.625, Model Delta =0.638= 0.638, Model Beta =64.5%=0.645= 64.5\% = 0.645, and Model Alpha =1320=0.650= \frac{13}{20} = 0.650. Comparing these values yields 0.625<0.638<0.645<0.6500.625 < 0.638 < 0.645 < 0.650, which matches the order Model Gamma, Model Delta, Model Beta, Model Alpha.

Step-by-Step Solution

1
Convert each given fraction, percentage, and decimal into equivalent decimal values for direct comparison.
Model Alpha =1320=0.650= \frac{13}{20} = 0.650; Model Beta =64.5%=0.645= 64.5\% = 0.645; Model Gamma =58=0.625= \frac{5}{8} = 0.625; Model Delta =0.638= 0.638.
Converting all values to decimals standardizes the quantities so they can be compared easily by place value.
2
Compare the resulting decimal numbers from least to greatest.
0.625<0.638<0.645<0.6500.625 < 0.638 < 0.645 < 0.650
Comparing digits from left to right: all have 0.60.6 in the tenths place; comparing the hundredths place shows 2<3<4<52 < 3 < 4 < 5.
3
Map the sorted decimal values back to their original model designations.
Model Gamma (58\frac{5}{8}), Model Delta (0.6380.638), Model Beta (64.5%64.5\%), Model Alpha (1320\frac{13}{20}).
This establishes the required sequence from least to greatest.

Key Concept

Converting fractions, decimals, and percentages to a common format (decimals) to order rational numbers.
Question 5546Question

A landscape architect is designing a public park with a total area of 14,400 square feet14,400\text{ square feet}. The plan allocates space for a lawn, flowerbeds, and paved walkways in the ratio 7:3:27 : 3 : 2, respectively. How many more square feet of area are dedicated to the lawn than to the flowerbeds?

Show answer & explanation

Answer: 4,800

Answer

4,800 square feet
The sum of all ratio parts is 7+3+2=127 + 3 + 2 = 12. Dividing the total park area of 14,400 sq ft14,400\text{ sq ft} by 1212 gives 1,200 sq ft1,200\text{ sq ft} per ratio part. The lawn accounts for 77 parts (8,400 sq ft8,400\text{ sq ft}) and the flowerbeds account for 33 parts (3,600 sq ft3,600\text{ sq ft}). Subtracting the flowerbed area from the lawn area gives 8,4003,600=4,800 sq ft8,400 - 3,600 = 4,800\text{ sq ft}. Alternatively, taking the direct difference of 73=47 - 3 = 4 parts and multiplying by 1,200 sq ft1,200\text{ sq ft} gives 4,800 sq ft4,800\text{ sq ft}.

Step-by-Step Solution

1
Find the total number of equal ratio parts.
7+3+2=12 parts7 + 3 + 2 = 12\text{ parts}
The complete park area is divided into portions defined by the sum of all terms in the ratio.
2
Calculate the area corresponding to one ratio part.
14,40012=1,200 square feet per part\frac{14,400}{12} = 1,200\text{ square feet per part}
Dividing the total area by the total number of parts determines the size of a single unit part.
3
Determine the difference in ratio parts between the lawn and the flowerbeds.
73=4 parts7 - 3 = 4\text{ parts}
The lawn receives 7 parts and the flowerbeds receive 3 parts.
4
Multiply the difference in parts by the area per part.
4×1,200=4,800 square feet4 \times 1,200 = 4,800\text{ square feet}
Multiplying the difference in ratio units by the unit area yields the total excess area of the lawn over the flowerbeds.

Key Concept

Solving multi-part ratio word problems using unit rate allocation per ratio part.
Estimated Time:1m 15s
Question 5547Question

A woodworker starts with a wooden board of length LL inches. After cutting off a piece measuring 16.516.5 inches to build a shelf bracket, the remaining portion of the board is 48.548.5 inches long. Which of the following equations can be used to find LL, the original length of the wooden board in inches?

Show answer & explanation

Answer: L16.5=48.5L - 16.5 = 48.5

Answer

L16.5=48.5L - 16.5 = 48.5
The original length of the board is LL inches. Cutting off a piece measuring 16.516.5 inches decreases the total length by 16.516.5, which is written algebraically as L16.5L - 16.5. Since the remaining length is given as 48.548.5 inches, setting these equal produces the equation L16.5=48.5L - 16.5 = 48.5.

Step-by-Step Solution

1
Identify the given variables and quantities in the scenario
Initial length = LL, length cut off = 16.516.5, remaining length = 48.548.5
Establishing clear variables allows systematic setup of the algebraic model.
2
Translate the physical action into a mathematical operation
Cutting off a piece represents subtraction from the starting quantity: L16.5L - 16.5
Removal of a part from a whole corresponds to subtraction.
3
Equate the expression for remaining length to the given remaining value
L16.5=48.5L - 16.5 = 48.5
The remaining length after cutting is stated to be 48.548.5 inches.

Key Concept

Translating verbal removal scenarios into one-step subtraction equations
Estimated Time:1m 0s
Question 5548Question

A venue manager allocates a total hospitality budget of dd dollars for an upcoming music festival. If the manager divides this budget equally among 14 performing artists, each artist receives exactly $185\$185. Which of the following equations correctly models this situation to find the total budget dd?

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Answer: d14=185\frac{d}{14} = 185

Answer

The correct equation is d14=185\frac{d}{14} = 185, which expresses that the total budget dd divided equally among 14 artists yields $185\$185 per artist.
Equal distribution of a total quantity dd across 14 recipients is mathematically represented by dividing dd by 14. Setting this quotient equal to the per-person amount of $185\$185 yields the equation d14=185\frac{d}{14} = 185.

Step-by-Step Solution

1
Identify the given quantities and variable
Total budget = dd, number of equal shares = 1414, amount per share = $185\$185
Setting up an equation requires matching the verbal scenario to mathematical operations.
2
Translate equal sharing into an algebraic operation
The total budget dd divided by 1414 is written as d14\frac{d}{14}
Dividing a total quantity into equal parts corresponds to division.
3
Equate the expression to the given share amount
d14=185\frac{d}{14} = 185
Each share is given as $185\$185.

Key Concept

Translating verbal division scenarios into one-step linear equations
Question 5549Question

To decipher the damaged sections of the medieval ledger, paleographers analyzed the faded, intricate script, cataloged regional dialect variations, and translated forgotten trade terms.

Which of the following choices for the underlined portion best maintains standard English conventions?

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Answer: NO CHANGE

Answer

The original phrasing ('faded, intricate script, cataloged regional dialect variations, and translated') is correct as written.
The original text correctly places a comma between the coordinate adjectives 'faded' and 'intricate' because both independently describe the noun 'script'. Furthermore, it properly uses commas to separate all three parallel past-tense verb phrases ('analyzed...', 'cataloged...', and 'translated...').

Step-by-Step Solution

1
Evaluate the punctuation between the adjectives 'faded' and 'intricate'.
The adjectives are coordinate because you can insert 'and' between them ('faded and intricate script') or reverse their order ('intricate, faded script'). Therefore, a comma between them is required.
Coordinate adjectives modifying the same noun must be separated by a comma.
2
Check the parallel structure and series punctuation of the sentence predicate.
The sentence lists three parallel past-tense verb phrases: (1) analyzed the script, (2) cataloged regional dialect variations, and (3) translated forgotten trade terms.
Items in a simple series of three or more elements must be separated by commas, including a serial comma before the coordinating conjunction 'and'.

Key Concept

Commas with Coordinate Adjectives and Items in a Series
Estimated Time:1m 0s
Question 5550Question

At an auto dealership, 25\frac{2}{5} of the vehicles in the inventory are sedans, 35%35\% are SUVs, and the remaining 45 vehicles are trucks. What is the total number of vehicles in the dealership's inventory?

Show answer & explanation

Answer: 180

Answer

The total number of vehicles in the dealership's inventory is 180.
Converting 25\frac{2}{5} to a percentage yields 40%40\%. Adding the 40%40\% sedans and 35%35\% SUVs shows that 75%75\% of the inventory consists of sedans and SUVs. Consequently, the remaining 25%25\% of the inventory consists of trucks. Since there are 45 trucks, 25%25\% of the total inventory equals 45. Dividing 45 by 0.250.25 yields the total inventory of 180 vehicles.

Step-by-Step Solution

1
Convert fraction of sedans to a percentage
Sedans represent 40%40\% of the total inventory.
To combine the amounts easily, convert 25\frac{2}{5} to percentage form: 25=0.40=40%\frac{2}{5} = 0.40 = 40\%.
2
Calculate the combined percentage of sedans and SUVs
Sedans and SUVs together make up 75%75\% of the inventory.
Add the two percentages: 40%+35%=75%40\% + 35\% = 75\%.
3
Determine the remaining percentage representing trucks
Trucks make up 25%25\% of the inventory.
The entire inventory equals 100%100\%, so 100%75%=25%100\% - 75\% = 25\%.
4
Solve for the total number of vehicles
The total inventory is 180 vehicles.
Set up the equation 25% of Total=4525\% \text{ of Total} = 45, which gives 0.25×Total=450.25 \times \text{Total} = 45, so Total=450.25=180\text{Total} = \frac{45}{0.25} = 180.

Key Concept

Converting fractions to percentages to find an unknown total quantity from a remaining part
Question 5551Question

At a community theater, ticket sales for a weekend musical were divided among three ticket categories: advance online purchases, box office walk-ups, and discounted student passes. Advance online purchases accounted for 25\frac{2}{5} of total ticket sales, and box office walk-up sales accounted for 35%35\% of total ticket sales. If the remaining 125 tickets sold were discounted student passes, what was the total number of tickets sold for the musical?

Show answer & explanation

Answer: 500

Answer

The total number of tickets sold for the musical was 500.
Advance online tickets represent 25=40%\frac{2}{5} = 40\% of the total. Adding the 35%35\% from box office walk-ups gives 75%75\% of total sales accounted for. The remaining 25%25\% of sales corresponds to the 125 student passes. Setting 25%25\% of the total equal to 125 and solving gives a total of 500 tickets.

Step-by-Step Solution

1
Convert the fraction of advance online tickets to a percentage.
25=40100=40%\frac{2}{5} = \frac{40}{100} = 40\%
Converting all proportions to percentages allows for direct comparison and addition.
2
Calculate the combined percentage of advance online and box office ticket sales.
40%+35%=75%40\% + 35\% = 75\%
Adding the two known categories determines the total portion of non-student ticket sales.
3
Find the percentage corresponding to the discounted student passes.
100%75%=25%100\% - 75\% = 25\%
The sum of all categories must equal 100%100\% of total sales.
4
Set up an equation relating the remaining percentage to the total ticket count TT.
0.25×T=125    T=1250.25=5000.25 \times T = 125 \implies T = \frac{125}{0.25} = 500
Dividing the part by its corresponding percentage rate yields the whole amount.

Key Concept

Solving multi-step word problems involving conversions between fractions, percentages, and whole numbers.
Estimated Time:1m 30s
Question 5552Question

Although subterranean mycorrhizal networks transport vital nutrients between canopy trees, forest ecologists still struggle to map these fragile complex fungal threads, for their delicate structures break down rapidly when exposed to air.

Which of the following choices produces a grammatically correct sentence that properly uses commas?

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Answer: fragile, complex fungal threads, for their delicate structures break down rapidly

Answer

The correct choice is the option that places a comma between 'fragile' and 'complex', leaves 'fungal' unseparated, and includes a comma before the coordinating conjunction 'for'.
The correct answer accurately separates the coordinate adjectives 'fragile' and 'complex' with a single comma, refrains from putting a comma before the cumulative adjective 'fungal', and correctly places a comma prior to the coordinating conjunction 'for', which joins two complete independent clauses.

Step-by-Step Solution

1
Evaluate the adjectives preceding 'threads' to determine coordinate versus cumulative relationship.
'Fragile' and 'complex' are coordinate adjectives modifying 'fungal threads' (testable by reversing them: 'complex, fragile fungal threads' or inserting 'and': 'fragile and complex'), requiring a separating comma. 'Fungal' is a cumulative adjective directly classifying 'threads', so no comma belongs between 'complex' and 'fungal'.
Coordinate adjectives independently modify the noun and require a comma, whereas cumulative adjectives build upon each other without punctuation.
2
Analyze the clause structure surrounding the conjunction 'for'.
'forest ecologists still struggle to map these fragile, complex fungal threads' and 'their delicate structures break down rapidly when exposed to air' are both independent clauses.
When two independent clauses are connected by a coordinating conjunction (FANBOYS: for, and, nor, but, or, yet, so), a comma must precede the conjunction.

Key Concept

Commas with Coordinate Adjectives and Coordinating Conjunctions
Estimated Time:1m 0s
Question 5553Question

A chemist uses the algebraic formula E=2x2yzx+y2E = \frac{2x^2 - yz}{x + y^2} to determine the stability index of a synthesized compound. If x=4x = -4, y=3y = -3, and z=23z = \frac{2}{3}, what is the value of EE?

Show answer & explanation

Answer: 345\frac{34}{5}

Answer

345\frac{34}{5}
Substituting x=4x = -4, y=3y = -3, and z=23z = \frac{2}{3} into the numerator yields 2(4)2(3)(23)=2(16)(2)=32+2=342(-4)^2 - (-3)\left(\frac{2}{3}\right) = 2(16) - (-2) = 32 + 2 = 34. Substituting into the denominator yields 4+(3)2=4+9=5-4 + (-3)^2 = -4 + 9 = 5. Thus, the value of the expression is 345\frac{34}{5}.

Step-by-Step Solution

1
Substitute the given values into the numerator 2x2yz2x^2 - yz.
2(4)2(3)(23)=2(16)(2)=32+2=342(-4)^2 - (-3)\left(\frac{2}{3}\right) = 2(16) - (-2) = 32 + 2 = 34
Squaring a negative number yields a positive result (4)2=16(-4)^2 = 16, and multiplying 3-3 by 23\frac{2}{3} gives 2-2, which is then subtracted.
2
Substitute the given values into the denominator x+y2x + y^2.
4+(3)2=4+9=5-4 + (-3)^2 = -4 + 9 = 5
Evaluating the exponent first gives (3)2=9(-3)^2 = 9, then adding 4-4 gives 55.
3
Divide the numerator by the denominator.
345\frac{34}{5}
Combine the evaluated numerator and denominator to get the final value of the expression.

Key Concept

Evaluating algebraic expressions involving multiple variables with negative bases and fractional terms using standard order of operations.
Estimated Time:1m 15s
Question 5554Question

If a=2a = -2, b=3b = 3, and c=12c = -\frac{1}{2}, what is the value of the algebraic expression a3b+4ca22b\frac{a^3 b + 4c}{a^2 - 2b}?

Fill in the blanks below

If a=2a = -2, b=3b = 3, and c=12c = -\frac{1}{2}, the value of the algebraic expression a3b+4ca22b\frac{a^3 b + 4c}{a^2 - 2b} is .
Show answer & explanation

Answer

13
Substituting a=2a = -2, b=3b = 3, and c=12c = -\frac{1}{2} into the given expression yields a numerator of (2)3(3)+4(12)=242=26(-2)^3(3) + 4(-\frac{1}{2}) = -24 - 2 = -26 and a denominator of (2)22(3)=46=2(-2)^2 - 2(3) = 4 - 6 = -2. Dividing the numerator by the denominator gives 262=13\frac{-26}{-2} = 13.

Step-by-Step Solution

1
Evaluate the terms in the numerator individually.
a3b=(2)33=83=24a^3 b = (-2)^3 \cdot 3 = -8 \cdot 3 = -24 and 4c=4(12)=24c = 4\left(-\frac{1}{2}\right) = -2.
Exponents take precedence before multiplication, and multiplying a positive by a negative yields a negative number.
2
Combine the terms to calculate the numerator.
Numerator =24+(2)=26= -24 + (-2) = -26.
Adding two negative numbers sums their magnitudes with a negative sign.
3
Evaluate the terms in the denominator.
a2=(2)2=4a^2 = (-2)^2 = 4 and 2b=2(3)=62b = 2(3) = 6.
Squaring a negative base results in a positive value.
4
Calculate the denominator.
Denominator =46=2= 4 - 6 = -2.
Subtracting a larger number from a smaller number produces a negative result.
5
Divide the numerator by the denominator to find the final value.
262=13\frac{-26}{-2} = 13.
Dividing a negative number by a negative number yields a positive quotient.

Key Concept

Evaluating Algebraic Expressions
Estimated Time:1m 30s
Question 5555Question

If x=3x = -3 and y=2y = 2, what is the value of the algebraic expression x2y(xy)22x+y2\frac{x^2 y - (x - y)^2}{2x + y^2}?

Show answer & explanation

Answer: 72\frac{7}{2}

Answer

72\frac{7}{2}
Substituting x=3x = -3 and y=2y = 2 gives a numerator of (3)2(2)(32)2=1825=7(-3)^2(2) - (-3 - 2)^2 = 18 - 25 = -7 and a denominator of 2(3)+22=6+4=22(-3) + 2^2 = -6 + 4 = -2. Dividing 7-7 by 2-2 gives 72\frac{7}{2}.

Step-by-Step Solution

1
Evaluate the terms in the numerator
x2y=(3)2(2)=92=18x^2 y = (-3)^2(2) = 9 \cdot 2 = 18 and (xy)2=(32)2=(5)2=25(x - y)^2 = (-3 - 2)^2 = (-5)^2 = 25
Apply order of operations by performing parenthetical subtraction before squaring negative numbers.
2
Subtract the terms to find the total numerator value
1825=718 - 25 = -7
Subtract the squared binomial result from the first product.
3
Evaluate the denominator
2x+y2=2(3)+22=6+4=22x + y^2 = 2(-3) + 2^2 = -6 + 4 = -2
Multiply and square the variable values before adding.
4
Divide the numerator by the denominator and simplify
72=72\frac{-7}{-2} = \frac{7}{2}
Dividing a negative number by a negative number yields a positive result.

Key Concept

Evaluating Algebraic Expressions with Negative Bases and Parentheses
Estimated Time:1m 0s
Question 5556Question

If x=2x = -2, y=13y = \frac{1}{3}, and z=4z = -4, what is the value of the algebraic expression x3y1(xz)2x+yz\frac{x^3 y^{-1} - (x - z)^2}{x + y z}?

Show answer & explanation

Answer: 425\frac{42}{5}

Answer

425\frac{42}{5}
Substituting x=2x = -2, y=13y = \frac{1}{3}, and z=4z = -4 into the expression yields (2)3=8(-2)^3 = -8, (13)1=3(\frac{1}{3})^{-1} = 3, and (2(4))2=22=4(-2 - (-4))^2 = 2^2 = 4. Thus, the numerator equals 8×34=28-8 \times 3 - 4 = -28. The denominator equals 2+(13)(4)=243=103-2 + (\frac{1}{3})(-4) = -2 - \frac{4}{3} = -\frac{10}{3}. Dividing the numerator by the denominator gives 28103=8410=425\frac{-28}{-\frac{10}{3}} = \frac{84}{10} = \frac{42}{5}.

Step-by-Step Solution

1
Substitute the given values into the numerator of the expression: x3y1(xz)2x^3 y^{-1} - (x - z)^2.
Numerator = (2)3(13)1(2(4))2=(8)(3)(2)2=244=28(-2)^3 \left(\frac{1}{3}\right)^{-1} - (-2 - (-4))^2 = (-8)(3) - (2)^2 = -24 - 4 = -28.
First apply exponent rules and basic arithmetic inside the parentheses following standard order of operations.
2
Substitute the given values into the denominator of the expression: x+yzx + y z.
Denominator = 2+(13)(4)=243=6343=103-2 + \left(\frac{1}{3}\right)(-4) = -2 - \frac{4}{3} = -\frac{6}{3} - \frac{4}{3} = -\frac{10}{3}.
Multiply yy and zz first, then find a common denominator to add the fraction to the integer.
3
Divide the simplified numerator by the simplified denominator.
\frac{-28}{-\frac{10}{3}} = -28 \times \left(-\frac{3}{10}\right) = \frac{84}{10} = \frac{42}{5}.
Dividing by a fraction is equivalent to multiplying by its reciprocal.

Key Concept

Evaluating Algebraic Expressions with Negative Numbers and Negative Exponents
Estimated Time:1m 15s
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