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