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Zorluk: OrtaMultiplying Polynomials

Determine the value of the missing coefficient by evaluating the problem below.

Cevap:A rectangular solar panel has a length of (5k−4)(5k - 4) inches and a width of (3k+7)(3k + 7) inches. The area of the panel is represented by the fully expanded polynomial Ak2+Bk+CAk^2 + Bk + C square inches. The value of the coefficient BB is 【23】.

Cevap

23
By multiplying the binomials (5k−4)(5k - 4) and (3k+7)(3k + 7), the expanded expression is 15k2+35k−12k−2815k^2 + 35k - 12k - 28. Combining the middle terms (35k−12k35k - 12k) yields 23k23k. Since the polynomial is in the standard form Ak2+Bk+CAk^2 + Bk + C, the value of BB is 23.

Adım Adım Çözüm

1
Set up the area calculation by multiplying the length and width binomials.
Area = (5k−4)(3k+7)(5k - 4)(3k + 7)
The area of a rectangle is found by multiplying its length by its width.
2
Distribute the terms using the FOIL method (First, Outer, Inner, Last).
15k2+35k−12k−2815k^2 + 35k - 12k - 28
Each term in the first binomial must be multiplied by each term in the second binomial.
3
Combine the like terms in the middle to find the value of BB.
15k2+23k−2815k^2 + 23k - 28
Adding 35k35k and −12k-12k simplifies the polynomial to the standard form Ak2+Bk+CAk^2 + Bk + C.
4
Identify the coefficient BB corresponding to the kk term.
B=23B = 23
The polynomial is 15k2+23k−2815k^2 + 23k - 28, so the coefficient of the kk term is 23.

Anahtar Kavram

Multiplying binomials and combining like terms to find a specific coefficient.
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