Question

Multiply. (5x+7)^2 :)

Answer 1

The answer is B.

Explanation:

You can expand it in a simplier way using :

`{(a + b)}^(2) = {a}^(2) + 2ab + {b}^(2)`

So for this question :

`{(5x + 7)}^(2) \\ = {(5x)}^(2) + 2(5x)(7) + {(7)}^(2) \\ = 25 {x}^(2) + 70x + 49`

Answer 2

B. 25x^2+70x+49

Explanation:

To multiply we can use a method called FOIL. In this method, we multiply the first terms of each binomial, then the outer terms (first and last), then the inner terms (2nd and 3rd), and finally the last terms (2nd and last). The two binomials in this case are (5x+7)(5x+7).

So this means we first multiply 5x*5x, then 5x*7, then 7*5x, and finally 7*7. Multiplying these out we get 25x^2 + 35x + 35x +49. Finally, combining like terms we get 25x^2+70x+49, which is our answer.