Question

question
express (x + 9)² as a trinomial in standard form.
answer attempt 1 out of 2

Explanation:

Step1: Expand using square formula

$(a+b)^2 = a^2 + 2ab + b^2$, here $a=x$, $b=9$

Step2: Substitute values into formula

$x^2 + 2(x)(9) + 9^2$

Step3: Simplify each term

$x^2 + 18x + 81$

Answer:

$x^2 + 18x + 81$