Solve for x
x=75
x=3
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\frac{x+27}{2}-6=\sqrt{27x}
Subtract 6 from both sides of the equation.
x+27-12=2\sqrt{27x}
Multiply both sides of the equation by 2.
x+15=2\sqrt{27x}
Subtract 12 from 27 to get 15.
\left(x+15\right)^{2}=\left(2\sqrt{27x}\right)^{2}
Square both sides of the equation.
x^{2}+30x+225=\left(2\sqrt{27x}\right)^{2}
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+15\right)^{2}.
x^{2}+30x+225=2^{2}\left(\sqrt{27x}\right)^{2}
Expand \left(2\sqrt{27x}\right)^{2}.
x^{2}+30x+225=4\left(\sqrt{27x}\right)^{2}
Calculate 2 to the power of 2 and get 4.
x^{2}+30x+225=4\times 27x
Calculate \sqrt{27x} to the power of 2 and get 27x.
x^{2}+30x+225=108x
Multiply 4 and 27 to get 108.
x^{2}+30x+225-108x=0
Subtract 108x from both sides.
x^{2}-78x+225=0
Combine 30x and -108x to get -78x.
a+b=-78 ab=225
To solve the equation, factor x^{2}-78x+225 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,-225 -3,-75 -5,-45 -9,-25 -15,-15
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 225.
-1-225=-226 -3-75=-78 -5-45=-50 -9-25=-34 -15-15=-30
Calculate the sum for each pair.
a=-75 b=-3
The solution is the pair that gives sum -78.
\left(x-75\right)\left(x-3\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=75 x=3
To find equation solutions, solve x-75=0 and x-3=0.
\frac{75+27}{2}=\sqrt{27\times 75}+6
Substitute 75 for x in the equation \frac{x+27}{2}=\sqrt{27x}+6.
51=51
Simplify. The value x=75 satisfies the equation.
\frac{3+27}{2}=\sqrt{27\times 3}+6
Substitute 3 for x in the equation \frac{x+27}{2}=\sqrt{27x}+6.
15=15
Simplify. The value x=3 satisfies the equation.
x=75 x=3
List all solutions of x+15=2\sqrt{27x}.
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