SOLUTION: Solve the quadratic equation 2x^2-8x-3=0 by completing the square. Write the expression as a single logarithm. 3[logx+2logy]-log(x-5)

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Solve the quadratic equation 2x^2-8x-3=0 by completing the square. Write the expression as a single logarithm. 3[logx+2logy]-log(x-5)       Log On


   

Question 397298: Solve the quadratic equation 2x^2-8x-3=0 by completing the square.

Write the expression as a single logarithm.
3[logx+2logy]-log(x-5)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the quadratic equation 2x^2-8x-3=0 by completing the square.
2x^2-8x = 3
2(x^2-4x+4) = 3+2*4
2(x-2)^2 = 11
(x-2)^2 = 11/2
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x-2 = 11sqrt(2)/2 or x-2 = -11sqrt(2)/2
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x = 2 + (11/2)sqrt(2) or x = 2 - (11/2)sqrt(2)
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Write the expression as a single logarithm.
3[logx+2logy]-log(x-5)
3[log(x)+log(y^2)] - log(x-5)
3[log(xy^2)] - log(x-5)
= log(x^3y^6/(x-5)]