SOLUTION: 3x^2+40x-128=0

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Question 970265: 3x^2+40x-128=0
Found 2 solutions by ankor@dixie-net.com, MathLover1:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
3x^2 + 40x - 128 = 0
you can use the quadratic formula a=3; b=40; c=-128, but this will factor to
(3x - 8)(x + 16) = 0
3x = 8
x = 22%2F3
and
x = -16

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

3x%5E2%2B40x-128=0....write 40x as -8x%2B48x
3x%5E2-8x%2B48x-128=0...group
%283x%5E2-8x%29%2B%2848x-128%29=0
x%283x-8%29%2B16%283x-8%29=0
%28x%2B16%29%283x-8%29+=+0
solutions:
if %28x%2B16%29+=+0, then x=-16
if %283x-8%29+=+0, then x=8%2F3

+graph%28+600%2C+600%2C+-20%2C+20%2C+-130%2C+20%2C3x%5E2-8x%2B48x-128%29+