Question

I am factoring. I know that I have to multiply (ac) 9(-4) = -36 factors there of are 1, -36; 2,-18; 3,-12; 4,-9 or -1,36; -2,18; -3,12; -4,9 9t^2 +5 - 4= (3t - 1)3t + (3t -1) - 4 Is this correct so far? Because after this I get lost

Answer 1

what's your original equation?

Answer 2

9t^2 + 5t - 4

Answer 3

lets go step by step, what have you determined your factors to be?

Answer 4

9, -4

Answer 5

sorry other way.. -9,4

Answer 6

no its 9 and -4 see the 5 is positive, indicating that the larger factor is positive

Answer 7

because I know that I have to have two integers with a product of -36 and the sum of 5

Answer 8

man i was right the first time... :(

Answer 9

yes you were, now the equation can be re-written as:
9t^2 +9t-4t-4, right?

Answer 10

(3t +1)3t + (3t+1)-4? Is this set up correctly?

Answer 11

no, look at it this way. you can now factor the first two terms separately and the last two separately, like this

Answer 12

or would it be like this (3t +1)3t + (3t+4)-1?

Answer 13

nope, relax,let me show you

Answer 14

ok

Answer 15

\[9t(t+1)-4(t+1)\
does this make any sense now?

Answer 16

no not really.... because when I work this out shouldn't it equal the original equation once the factorization has been completed?

Answer 17

yep, \[9t(t+1)-4(t+1)\]
are you multiplying correctly?

Answer 18

I get 9t^2 + 9t - 4t -4
simplified 9t^2 + 5t - 4

lol ok so I am retarded or more like frustrated.. :) thank you for your assistance...:D

Answer 19

you welcome,but remember you've not yet factored it,
see the common (t+1), you ignore one and it becomes::
(9t-4)(t+1) and that's the factored expression

Answer 20

so the total expression should look like this:
9t^2 +5t - 4 =
9t(t+1) -4(t+1) =
(9t-4)(t+1)

Answer 21

right

Answer 22

:D you are awesome!!!!!!