Question

Which of the following values "completes the square," or creates a perfect square trinomial, for x2 + 10x + ___? 25 10 5 –5

Answer 1

"completes the square," or creates a perfect square trinomial, for x2 + 10x + ___

$x^2 + 10x +____$

To complete the square , we take half of coefficient of middle term and then we square it. Here middle term is 10x.

Coefficient of middle term is 10

Half of 10 is 5

Then square of 5 is 25

We add 25 to get perfect square trinomial

$x^2 + 10x + 25$

$(x+5)(x+5)$

$(x+5)^2$

So 25 is the answer