SOLUTION: Solve for x in terms of k. log_(7) x + log_(7) (x+10) = k.

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Question 925162: Solve for x in terms of k.
log_(7) x + log_(7) (x+10) = k.

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x in terms of k.
log_(7) x + log_(7) (x+10) = k.
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log%287%2C%28x%29%29%2Blog%287%2C%28x%2B10%29%29=k
log%287%2C%28%28x%29%28x%2B10%29%29%29=k
base(7)raised to log of number(k)=number(x(x+10))
7^k=x(x+10)=x^2+10x
x^2+10x-7^k=0
solve for x by quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=10, c=7^k
x+=+%28-10+%2B-+sqrt%28+100-4%2A1%2A7%5Ek+%29%29%2F%282%29+
x+=+%28-10+%2B-+sqrt%28+100-4%2A7%5Ek+%29%29%2F%282%29+