SOLUTION: Hi, would you pls, explain to me, how 2 do this: Solve for x : 2x^2 – 5x = 12 I started like this : 2x^2 – 5x -12 = 0 but lost it after ... Thanks a lot.

Algebra ->  Graphs -> SOLUTION: Hi, would you pls, explain to me, how 2 do this: Solve for x : 2x^2 – 5x = 12 I started like this : 2x^2 – 5x -12 = 0 but lost it after ... Thanks a lot.      Log On


   

Question 604839: Hi,
would you pls, explain to me, how 2 do this:
Solve for x : 2x^2 – 5x = 12
I started like this : 2x^2 – 5x -12 = 0 but lost it after ...
Thanks a lot.
Answer by alicealc(293) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2-5x-12=0
Find 2 numbers a and b so that
a*b = 2*(-12) =-24
and
a+b = -5
the numbers are -8 and 3
-8 is divisible by 2 -> -8/2 = -4

2x^2 can be separated as 2x*x

so, the factorization will be:
(2x + 3)(x - 4)=0
2x + 3 = 0 or x - 4 = 0
2x = -3 or x = 4
x = -3/2 or x = 4