Question

Solve (x + 3)(x – 3) = 40. Identify any double roots.

A. {3, –3}

B. {7, –7}

C. {0, 3, –3}

D. {0, 7 (double root)}

Answer 1

Please anyone help!:(

Answer 2

so FOIL

Answer 3

First expand the factored expression and then bring the 40 over to the other side so the whole expression equals 0 and then re-factor to get the x-intercepts, like this:\[(x+3)(x-3)=40 \rightarrow x^2-9=40 \rightarrow x^2-49 = 0 \rightarrow (x-7)(x+7)=0\]\[\implies x = \pm7\]

Answer 4

@RH

Answer 5

Therefore, the answer is B. {7, -7} @RH

Answer 6

yeah {7,-7} i had that also :)

Answer 7

Thank you both a lot!!!!!!!! :)

Answer 8

no problem :)

Answer 9

Lol medal/fan? @RH =[

Answer 10

^hahah yeaH?

Answer 11

Well, you both deserve it, but I am going to be fair and give it to @some_someone because he/she answered first. I am sorry @genius12 . But I thank you both because I understood it quite well.

Answer 12

thanks :}