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# Factor trinomial $$ \color{blue}{ x^2+10x+25 } $$

## Answer

The factored form is $$ \color{blue}{ x^2+10x+25 = \left(x+5\right)^2 } $$

## Explanation

Both the first and third terms are perfect squares.

$$ x^2 = \left( \color{blue}{ x } \right)^2 ~~ \text{and} ~~ 25 = \left( \color{red}{ 5 } \right)^2 $$

The middle term ( $ 10x $ ) is two times the product of the terms that are squared.

$$ 10x = 2 \cdot \color{blue}{x} \cdot \color{red}{5} $$

We can conclude that the polynomial $ x^{2}+10x+25 $ is a **perfect square trinomial**, so we will use the formula below.

$$ A^2 + 2AB + B^2 = (A + B)^2 $$

In this example we have $ \color{blue}{ A = x } $ and $ \color{red}{ B = 5 } $ so,

$$ x^{2}+10x+25 = ( \color{blue}{ x } + \color{red}{ 5 } )^2 $$