Solve for x
x=28
x=-28
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88704=\frac{792}{7}x^{2}
Multiply \frac{22}{7} and 36 to get \frac{792}{7}.
\frac{792}{7}x^{2}=88704
Swap sides so that all variable terms are on the left hand side.
\frac{792}{7}x^{2}-88704=0
Subtract 88704 from both sides.
x^{2}-784=0
Divide both sides by \frac{792}{7}.
\left(x-28\right)\left(x+28\right)=0
Consider x^{2}-784. Rewrite x^{2}-784 as x^{2}-28^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=28 x=-28
To find equation solutions, solve x-28=0 and x+28=0.
88704=\frac{792}{7}x^{2}
Multiply \frac{22}{7} and 36 to get \frac{792}{7}.
\frac{792}{7}x^{2}=88704
Swap sides so that all variable terms are on the left hand side.
x^{2}=88704\times \frac{7}{792}
Multiply both sides by \frac{7}{792}, the reciprocal of \frac{792}{7}.
x^{2}=784
Multiply 88704 and \frac{7}{792} to get 784.
x=28 x=-28
Take the square root of both sides of the equation.
88704=\frac{792}{7}x^{2}
Multiply \frac{22}{7} and 36 to get \frac{792}{7}.
\frac{792}{7}x^{2}=88704
Swap sides so that all variable terms are on the left hand side.
\frac{792}{7}x^{2}-88704=0
Subtract 88704 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times \frac{792}{7}\left(-88704\right)}}{2\times \frac{792}{7}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{792}{7} for a, 0 for b, and -88704 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{792}{7}\left(-88704\right)}}{2\times \frac{792}{7}}
Square 0.
x=\frac{0±\sqrt{-\frac{3168}{7}\left(-88704\right)}}{2\times \frac{792}{7}}
Multiply -4 times \frac{792}{7}.
x=\frac{0±\sqrt{40144896}}{2\times \frac{792}{7}}
Multiply -\frac{3168}{7} times -88704.
x=\frac{0±6336}{2\times \frac{792}{7}}
Take the square root of 40144896.
x=\frac{0±6336}{\frac{1584}{7}}
Multiply 2 times \frac{792}{7}.
x=28
Now solve the equation x=\frac{0±6336}{\frac{1584}{7}} when ± is plus. Divide 6336 by \frac{1584}{7} by multiplying 6336 by the reciprocal of \frac{1584}{7}.
x=-28
Now solve the equation x=\frac{0±6336}{\frac{1584}{7}} when ± is minus. Divide -6336 by \frac{1584}{7} by multiplying -6336 by the reciprocal of \frac{1584}{7}.
x=28 x=-28
The equation is now solved.
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