Question

A student factors 15c^2 + c – 28 to the following.

(c + 2)(15c – 14)

Which of the following statement about (c + 2)(15c – 14) is true?
A. The expression is equivalent, and it is completely factored.
B. The expression is equivalent, but it is not completely factored.
C. The expression is not equivalent, but it is completely factored.
D.The expression is not equivalent, and it is not completely factored.

Answer 1

Answer : C. The expression is not equivalent, but it is completely factored.

`15c^2 + c - 28` can be factored

15 * -28 = -420

21 and -20 are the factors whose sum is +1 and product is -420

`15c^2 -20c + 21c - 28`

`(15c^2 -20c) +(21c - 28)`

`5c(3c -4) + 7(3c - 4)`

`(5c+7)(3c -4)`

This is not equivalent to (c + 2)(15c - 14)

But (c + 2)(15c – 14) is completely factored

So , The expression is not equivalent, but it is completely factored.

Answer 2

The expression is not equivalent, but it is completely factored.