SOLUTION: solve log(7x^2+30x+2) - 2log(x+1) = 1

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Question 134410: solve log(7x^2+30x+2) - 2log(x+1) = 1
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
Given : log(7x^2+30x+2) - 2log(x+1) = 1
Use the values on both side and raise 10 to that number
10%5E%28log%287x%5E2%2B30x%2B2%29+-+2log%28x%2B1%29%29+=+10%5E1
%2810%5E%28log%287x%5E2%2B30x%2B2%29%29%29%2F%2810%5E%282log%28x%2B1%29%29%29+=+10
%287x%5E2%2B30x%2B2%29%2F%28%28x%2B1%29%5E2%29+=+10
%287x%5E2%2B30x%2B2%29=+10%28x%2B1%29%5E2
7x%5E2%2B30x%2B2+=+10x%5E2+%2B+20x+%2B+10
0+=+3x%5E2+-10x+%2B+8
Use the quadratic equation
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Find x = 2, x = 8/6
Check by subbing back into the original equation and using your calculator