SOLUTION: 2x^(3)+7x^(2)+8x+3=0

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Question 1122880: 2x^(3)+7x^(2)+8x+3=0
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

2x%5E3%2B7x%5E2%2B8x%2B3=0...factor completely; write 7x%5E2 as 3x%5E2%2B4x%5E2, and 8x as 6x%2B2x
2x%5E3%2B3x%5E2%2B4x%5E2%2B6x%2B2x%2B3=0...group
%282x%5E3%2B3x%5E2%29%2B%284x%5E2%2B6x%29%2B%282x%2B3%29=0
x%5E2%282x%2B3%29%2B2x%282x%2B3%29%2B%282x%2B3%29=0
%28x%5E2%2B2x+%2B+1%29+%282x+%2B+3%29+=+0
%28x+%2B+1%29%5E2+%282x+%2B+3%29+=+0
solutions:
if %28x+%2B+1%29%5E2+=+0->x=-1
%282x+%2B+3%29+=+0->2x=-3->x=-3%2F2

+graph%28+600%2C+600%2C+-5%2C+5%2C+-5%2C+5%2C2x%5E3%2B7x%5E2%2B8x%2B3%29+