(x+2)^2-(x+7)^2 Using a^2-b^2=(a+b)(a-b)
Answer from the book is -5(2x+9)
I cannot get there from here. If anyone has time, could you please explain how to arrive at that answer?

Question

(x+2)^2-(x+7)^2    Using a^2-b^2=(a+b)(a-b)
Answer from the book is -5(2x+9)
I cannot get there from here. If anyone has time, could you please explain how to arrive at that answer?

zzr0ck3r · Answer

$(x+2)^2-(x+7)^2=\x^2+4x+4-(x^2+14x+49=\x^2+4x+4-x^2-14x-49=\-10x-45=-5(2x+9)$

anonymous · Answer

$$\left( x+2 \right)^2-\left( x+7 \right)^2=\left\{ x+2+x+7\right\}\left\{ x+2-\left( x+7 \right) \right\}$$
$$=(2x+9)(x+2-x-7)=-5(2x+9)$$

zzr0ck3r · Answer

weird use of set brackets:)

anonymous · Answer

Thank you both! Why can't I give best response to both? What a crock, you both helped.

zzr0ck3r · Answer

give it to @surjithayer , his\hers was pretty

anonymous · Answer

Done! Thank you both again, its whipping me but with help Im getting the hang of it.

anonymous · Answer

yw. i am a man.

zzr0ck3r · Answer

I should delete my comment, then it would make that last statement seem strange.