Solve for x
x = \frac{400}{49 \pi} \approx 2.59844805
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\pi x\times 7^{2}=400
Multiply both sides of the equation by 4.
\pi x\times 49=400
Calculate 7 to the power of 2 and get 49.
49\pi x=400
The equation is in standard form.
\frac{49\pi x}{49\pi }=\frac{400}{49\pi }
Divide both sides by 49\pi .
x=\frac{400}{49\pi }
Dividing by 49\pi undoes the multiplication by 49\pi .
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