Solve for x
x=0
x=49
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\left(\sqrt{x}\right)^{2}=\left(\frac{x}{7}\right)^{2}
Square both sides of the equation.
x=\left(\frac{x}{7}\right)^{2}
Calculate \sqrt{x} to the power of 2 and get x.
x=\frac{x^{2}}{7^{2}}
To raise \frac{x}{7} to a power, raise both numerator and denominator to the power and then divide.
x=\frac{x^{2}}{49}
Calculate 7 to the power of 2 and get 49.
x-\frac{x^{2}}{49}=0
Subtract \frac{x^{2}}{49} from both sides.
49x-x^{2}=0
Multiply both sides of the equation by 49.
-x^{2}+49x=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-49±\sqrt{49^{2}}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 49 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-49±49}{2\left(-1\right)}
Take the square root of 49^{2}.
x=\frac{-49±49}{-2}
Multiply 2 times -1.
x=\frac{0}{-2}
Now solve the equation x=\frac{-49±49}{-2} when ± is plus. Add -49 to 49.
x=0
Divide 0 by -2.
x=-\frac{98}{-2}
Now solve the equation x=\frac{-49±49}{-2} when ± is minus. Subtract 49 from -49.
x=49
Divide -98 by -2.
x=0 x=49
The equation is now solved.
\sqrt{0}=\frac{0}{7}
Substitute 0 for x in the equation \sqrt{x}=\frac{x}{7}.
0=0
Simplify. The value x=0 satisfies the equation.
\sqrt{49}=\frac{49}{7}
Substitute 49 for x in the equation \sqrt{x}=\frac{x}{7}.
7=7
Simplify. The value x=49 satisfies the equation.
x=0 x=49
List all solutions of \sqrt{x}=\frac{x}{7}.
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