Question

r^2-9
factor
medals will be awarded

Answer 1

Alright, you're going to walk through this one with me.

Answer 2

1/r^7

Answer 3

Notice that r^2 - 9 is the same thing as r^2 + 0 r -9

Answer 4

You're looking for two numbers, a and b, that multiply to get -9 and add up to get 0.

Answer 5

ok...I am tracking...just a little.

Answer 6

Tracking?

Answer 7

What are two numbers that multiply together to get -9?

Answer 8

3 and -3

Answer 9

Awesome. Do they add up to 0?

Answer 10

um I think so...that part confuses me a little

Answer 11

3+(-3) =

Answer 12

It does equal zero :) . As long as you have two numbers that multiply together to get -9 and add up to get 0, you have the right numbers.

We just fill in (x-3)(x+3) and we're done!

Answer 13

ok...I am still a little confused but a little less than before. Thank you. I will still be posting problems though, they are all the ones I had problems with.

Answer 14

Alrighty. We can walk through another one. After a couple more, I think you'll have the hang of it. One problem won't be enough, but a couple more might.

Answer 15

ok thank you...

Answer 16

Lol, couldn't tell if that was sarcastic or not. The help is there if you want it, but I won't shove it down your throat if you don't.

Answer 17

r^2+0*r-9
find two factors of -9 that multiply to be -9 and add up to be 0
-3(3)=-9 and -3+3=0

r^2-3r+3r-9

factor by grouping

r(r-3)+3(r-3)

(r-3)(r+3)

Answer 18

Good work guys. I think this one is taught (or learned) better by 'difference of two squares.'