SOLUTION: 2x^3+x^2-61x+30=0

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Question 1084540: 2x^3+x^2-61x+30=0
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E3%2Bx%5E2-61x%2B30=0.... factor first; write x%5E2 as -10x%5E2-x%5E2%2B12x%5E2 and -61x as 5x-60x-6x
2x%5E3-10x%5E2+-x%5E2%2B5x%2B12x%5E2-60x-6x%2B30+=+0........group
%282x%5E3-10x%5E2%29+-%28x%5E2-5x%29%2B%2812x%5E2-60x%29-%286x-30%29+=+0
2x%5E2%28x-5%29+-+x%28x-5%29%2B12x%28x-5%29-6%28x-5%29+=+0
%28x+-+5%29%282x%5E2+-x%2B12x-6%29+=+0
%28x+-+5%29%28%282x%5E2+-x%29%2B%2812x-6%29%29+=+0
%28x+-+5%29%28x%282x+-1%29%2B6%282x-1%29%29+=+0
%28x+-+5%29+%28x+%2B+6%29+%282x+-+1%29+=+0
roots:
if %28x+-+5%29+=+0-> x=5
if +%28x+%2B+6%29++=+0-> x=-6
if +%282x+-+1%29+=+0->2x=1->x=1%2F2




+graph%28+600%2C+600%2C+-10%2C+10%2C+-100%2C+150%2C2x%5E3%2Bx%5E2-61x%2B30%29+