Linear and Quadratic Inequalities

27 soru

Soru 21Soru →

Find the largest integer value of xx that satisfies the linear inequality 2x−53≤x+14\frac{2x - 5}{3} \le \frac{x + 1}{4}.

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Cevap: 4

Cevap

The largest integer value of xx satisfying the inequality is 4.
Multiplying the entire inequality by 12 yields 4(2x - 5) <= 3(x + 1). Expanding both sides produces 8x - 20 <= 3x + 3. Subtracting 3x and adding 20 gives 5x <= 23, which simplifies to x <= 4.6. The largest integer less than or equal to 4.6 is 4.

Adım Adım Çözüm

1
Clear the denominators by multiplying both sides by 12.
4(2x - 5) \le 3(x + 1)
Multiplying by a positive number preserves the inequality direction while clearing fractions.
2
Expand both sides of the inequality using the distributive property.
8x - 20 \le 3x + 3
Multiply 4 through (2x - 5) and 3 through (x + 1).
3
Isolate the variable terms on one side and constant terms on the other.
5x \le 23 \implies x \le 4.6
Subtract 3x from both sides and add 20 to both sides, then divide by 5.
4
Determine the maximum integer value satisfying the inequality boundary.
4
Since x must be less than or equal to 4.6, the greatest whole integer satisfying this condition is 4.

Anahtar Kavram

Solving linear inequalities with fractions and finding integer bounds
Soru 22Soru →

Find the sum of all integer values of xx that satisfy both the linear inequality 2x−1≥32x - 1 \ge 3 and the quadratic inequality x2−5x−14≤0x^2 - 5x - 14 \le 0.

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Cevap: 27

Cevap

The sum of all integer values of xx satisfying both inequalities is 2727.
Solving the linear inequality 2x−1≥32x - 1 \ge 3 yields x≥2x \ge 2. Solving the quadratic inequality x2−5x−14≤0x^2 - 5x - 14 \le 0 by factoring gives (x−7)(x+2)≤0(x - 7)(x + 2) \le 0, which defines the interval −2≤x≤7-2 \le x \le 7. Taking the intersection of x≥2x \ge 2 and −2≤x≤7-2 \le x \le 7 gives 2≤x≤72 \le x \le 7. The integer values satisfying this range are 2,3,4,5,6,2, 3, 4, 5, 6, and 77, and their sum is 2727.

Adım Adım Çözüm

1
Solve the linear inequality
2x≥4  ⟹  x≥22x \ge 4 \implies x \ge 2
Adding 1 to both sides and dividing by 2 isolates the variable xx.
2
Factor and solve the quadratic inequality
(x−7)(x+2)≤0  ⟹  −2≤x≤7(x - 7)(x + 2) \le 0 \implies -2 \le x \le 7
The roots of the quadratic equation are x=7x = 7 and x=−2x = -2. The parabola opens upward, so the expression is non-positive between the roots.
3
Determine the intersection of both solution sets
2≤x≤72 \le x \le 7
The values of xx must simultaneously satisfy x≥2x \ge 2 and −2≤x≤7-2 \le x \le 7.
4
List all integer solutions within the valid interval
x∈{2,3,4,5,6,7}x \in \{2, 3, 4, 5, 6, 7\}
These are all the whole numbers contained in the closed interval [2,7][2, 7].
5
Sum the integer solutions
2+3+4+5+6+7=272 + 3 + 4 + 5 + 6 + 7 = 27
Summing the identified integer values yields the final required numerical answer.

Anahtar Kavram

Linear and Quadratic Inequalities
Tahmini Süre:1m 30s
Soru 23Soru →

Find the set of real values of xx that satisfies the inequality 5−2x3≥x−5\frac{5 - 2x}{3} \ge x - 5.

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Cevap: x≤4x \le 4

Cevap

The set of real values satisfying the inequality is x≤4x \le 4.
Multiplying through by 33 yields 5−2x≥3x−155 - 2x \ge 3x - 15. Rearranging terms gives −5x≥−20-5x \ge -20. Dividing both sides by −5-5 requires flipping the inequality sign from ≥\ge to ≤\le, giving x≤4x \le 4.

Adım Adım Çözüm

1
Multiply both sides of the inequality by 3 to clear the fraction.
5−2x≥3(x−5)5 - 2x \ge 3(x - 5)
Eliminating the denominator simplifies the algebraic expression.
2
Expand the right-hand side and collect terms containing xx on one side and constants on the other.
5−2x≥3x−15  ⟹  −2x−3x≥−15−5  ⟹  −5x≥−205 - 2x \ge 3x - 15 \implies -2x - 3x \ge -15 - 5 \implies -5x \ge -20
Group like terms to isolate the variable xx.
3
Divide both sides by −5-5 and reverse the inequality sign.
x≤−20−5  ⟹  x≤4x \le \frac{-20}{-5} \implies x \le 4
Dividing or multiplying an inequality by a negative number reverses the direction of the inequality sign.

Anahtar Kavram

Solving linear inequalities involving negative coefficient division
Soru 24Soru →

Which of the following is the set of real values of xx that satisfies the inequality 3−x4≤2x+53\frac{3 - x}{4} \le \frac{2x + 5}{3}?

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Cevap: x≥−1x \ge -1

Cevap

The set of real values of xx that satisfies the inequality is x≥−1x \ge -1.
Multiplying through by 12 gives 9−3x≤8x+209 - 3x \le 8x + 20. Grouping terms results in −11x≤11-11x \le 11. Dividing by −11-11 requires reversing the inequality sign from ≤\le to ≥\ge, giving the solution x≥−1x \ge -1.

Adım Adım Çözüm

1
Clear the denominators by multiplying both sides of the inequality by the lowest common multiple, 12.
3(3−x)≤4(2x+5)3(3 - x) \le 4(2x + 5)
Eliminating fractions simplifies the algebraic expression.
2
Expand both sides by distributing the multipliers.
9−3x≤8x+209 - 3x \le 8x + 20
Prepares terms for grouping variables on one side and constants on the other.
3
Collect all terms containing xx on the left side and constant terms on the right side.
−3x−8x≤20−9  ⟹  −11x≤11-3x - 8x \le 20 - 9 \implies -11x \le 11
Isolates the linear variable term.
4
Divide both sides by −11-11 and flip the inequality sign.
x≥−1x \ge -1
Dividing or multiplying an inequality by a negative number reverses the direction of the inequality sign.

Anahtar Kavram

Linear Inequalities and Reversing Inequality Sign on Division by Negative Numbers
Soru 25Soru →

Determine the smallest integer value of xx that satisfies the compound inequality 3<2x−5≤113 < 2x - 5 \le 11.

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Cevap: 5

Cevap

The smallest integer value of xx that satisfies the inequality is 5.
Adding 5 across the compound inequality 3<2x−5≤113 < 2x - 5 \le 11 gives 8<2x≤168 < 2x \le 16. Dividing by 2 yields 4<x≤84 < x \le 8. The integer values satisfying this range are 5, 6, 7, and 8. Therefore, the smallest integer solution is 5.

Adım Adım Çözüm

1
Add 5 to all parts of the compound inequality
8 < 2x <= 16
Isolates the variable term in the middle segment.
2
Divide all parts of the compound inequality by 2
4 < x <= 8
Solves for x without changing inequality signs since 2 is positive.
3
Identify integer solutions within the range (4, 8]
x in {5, 6, 7, 8}
Since the inequality at 4 is strict (<), 4 is excluded, but 8 is included (<=).
4
Find the minimum integer value in the solution set
5
5 is the smallest integer strictly greater than 4.

Anahtar Kavram

Solving Compound Linear Inequalities
Soru 26Soru →

Which of the following represents the solution set of real values of xx satisfying the inequality 4(1−x)≤3(x+6)4(1 - x) \le 3(x + 6)?

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Cevap: x≥−2x \ge -2

Cevap

The set of real values satisfying the inequality is x≥−2x \ge -2.
Expanding the given inequality yields 4−4x≤3x+184 - 4x \le 3x + 18. Subtracting 3x3x and 44 from both sides gives −7x≤14-7x \le 14. When dividing both sides by −7-7, the inequality sign must reverse direction, yielding x≥−2x \ge -2.

Adım Adım Çözüm

1
Expand both sides of the inequality
4−4x≤3x+184 - 4x \le 3x + 18
Remove brackets to group like terms.
2
Rearrange terms by moving variable terms to the left side and constant terms to the right side
−4x−3x≤18−4  ⟹  −7x≤14-4x - 3x \le 18 - 4 \implies -7x \le 14
Isolate the term containing the variable xx.
3
Divide both sides by −7-7 and reverse the inequality sign
x≥−2x \ge -2
Dividing or multiplying an inequality by a negative number flips the direction of the inequality symbol.

Anahtar Kavram

Solving linear inequalities involving bracket expansion and division by negative numbers
Soru 27Soru →

How many integer values of xx satisfy the quadratic inequality 2x2−7x−4≤02x^2 - 7x - 4 \le 0?

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Cevap: 5

Cevap

There are 5 integer values of x that satisfy the inequality.
Solving the quadratic inequality yields −12≤x≤4-\frac{1}{2} \le x \le 4. The integer solutions within this interval are 0,1,2,3,0, 1, 2, 3, and 44. Counting them gives a total of 55 valid integer values.

Adım Adım Çözüm

1
Factor the quadratic expression.
(2x+1)(x−4)≤0(2x + 1)(x - 4) \le 0
Factoring allows determination of the critical boundary points.
2
Find the critical values (roots of the equation).
x=−12x = -\frac{1}{2} and x=4x = 4
The roots divide the number line into test intervals.
3
Determine the solution set of the inequality.
−12≤x≤4-\frac{1}{2} \le x \le 4
Since the quadratic coefficient is positive, the quadratic expression is non-positive between its roots.
4
List and count the integers within the range.
The integers are 0,1,2,3,40, 1, 2, 3, 4, making a total of 55 integers.
Counting only whole numbers in the closed interval [−0.5,4][ -0.5, 4 ].

Anahtar Kavram

Quadratic Inequalities and Integer Solution Counting
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