Question

r^2+13r-30=0 step by step please thanks

Answer 1

First step is to factor the polynomial.

Answer 2

ok.

Answer 3

whats the polynomial?

Answer 4

r^2+13r-30

Answer 5

r^2+13r-30 is the polynomial. A term is something like r^2 or 13r. when you have more than one term or two terms, or in this case 3 terms, it's a polynomial. SO the whole thing is a polynomial.

Answer 6

i could have sworn we just did this one...

Answer 7

and the way to find how r is = 0 is to use the factor method. so set up two blank sets of ( ) ( ) = 0

Answer 8

yeah but i asked questions no one responded i needed it explained further sorry

Answer 9

we did satellite. It's he needs explained further :)

Answer 10

oops ok sorry

Answer 11

so when you have ( ) ( ) = 0, you take your polynomial and go hmm. With all polynomails begging with something like r^2, you are going to need two r's in the ( ) ( )

Answer 12

Oh I remembered learning this lol just forgot how to, Im doing summer math problems and need my memory refreshed lol

Answer 13

so it should at first look like this, (r ) ( r ) = 0 I'm doing summer math too.

Answer 14

so those two R's are going to multiply in the end to make r^2, that's why this works. next you need two factors of 30 that multiply to make -30 and add to make 13r

Answer 15

oh yeah. so it's supposed to be equaled to the coefficient?

Answer 16

in the equation

Answer 17

yup, so r x r = r^2. So all the factors of 30? 30 and 1, 15 and 2, 5 and 6 ect

Answer 18

of those factors, can you see any two that would add or subtract to be 13?

Answer 19

6?

Answer 20

5 + 6 = 11. :P but 15-2 = 13

Answer 21

oohhh lol oops sorry

Answer 22

I remember now thanks so much for refreshing my memory xD

Answer 23

np XD. so if you know that 15-2 = 13 and 15x2 = 30 then you know what two numbers go in the ( ) ( ). So you should have (r 15) and (r 2) now. All that's left is to find which sign (eithr + or -) to put between!

Answer 24

no prob. take it easy. I really want subway right now. I should work on my precalc stuff

Answer 25

lol okay thanks again

Answer 26

im going to refer back to your explanation on the rest of these problems

Answer 27

are you there?