Solve for x
x=7
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\left(\sqrt{9x-28}\right)^{2}=\left(\sqrt{5x}\right)^{2}
Square both sides of the equation.
9x-28=\left(\sqrt{5x}\right)^{2}
Calculate \sqrt{9x-28} to the power of 2 and get 9x-28.
9x-28=5x
Calculate \sqrt{5x} to the power of 2 and get 5x.
9x-28-5x=0
Subtract 5x from both sides.
4x-28=0
Combine 9x and -5x to get 4x.
4x=28
Add 28 to both sides. Anything plus zero gives itself.
x=\frac{28}{4}
Divide both sides by 4.
x=7
Divide 28 by 4 to get 7.
\sqrt{9\times 7-28}=\sqrt{5\times 7}
Substitute 7 for x in the equation \sqrt{9x-28}=\sqrt{5x}.
35^{\frac{1}{2}}=35^{\frac{1}{2}}
Simplify. The value x=7 satisfies the equation.
x=7
Equation \sqrt{9x-28}=\sqrt{5x} has a unique solution.
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