Question

perform the indicated operations and simplify completely: $(x - 7)^2-(x + 7)^2$ answer =

Explanation:

Step1: Expand the squares

Use the formula $(a - b)^2=a^{2}-2ab + b^{2}$ and $(a + b)^2=a^{2}+2ab + b^{2}$.
$(x - 7)^2=x^{2}-14x + 49$ and $(x + 7)^2=x^{2}+14x + 49$.
So the expression becomes $(x^{2}-14x + 49)-(x^{2}+14x + 49)$.

Step2: Remove the parentheses

$x^{2}-14x + 49-x^{2}-14x - 49$.

Step3: Combine like - terms

$(x^{2}-x^{2})+(-14x-14x)+(49 - 49)$.
$-28x$.

Answer:

$-28x$