Solve for x
x=-40
x=40
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x^{2}+900=50^{2}
Calculate 30 to the power of 2 and get 900.
x^{2}+900=2500
Calculate 50 to the power of 2 and get 2500.
x^{2}+900-2500=0
Subtract 2500 from both sides.
x^{2}-1600=0
Subtract 2500 from 900 to get -1600.
\left(x-40\right)\left(x+40\right)=0
Consider x^{2}-1600. Rewrite x^{2}-1600 as x^{2}-40^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=40 x=-40
To find equation solutions, solve x-40=0 and x+40=0.
x^{2}+900=50^{2}
Calculate 30 to the power of 2 and get 900.
x^{2}+900=2500
Calculate 50 to the power of 2 and get 2500.
x^{2}=2500-900
Subtract 900 from both sides.
x^{2}=1600
Subtract 900 from 2500 to get 1600.
x=40 x=-40
Take the square root of both sides of the equation.
x^{2}+900=50^{2}
Calculate 30 to the power of 2 and get 900.
x^{2}+900=2500
Calculate 50 to the power of 2 and get 2500.
x^{2}+900-2500=0
Subtract 2500 from both sides.
x^{2}-1600=0
Subtract 2500 from 900 to get -1600.
x=\frac{0±\sqrt{0^{2}-4\left(-1600\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -1600 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1600\right)}}{2}
Square 0.
x=\frac{0±\sqrt{6400}}{2}
Multiply -4 times -1600.
x=\frac{0±80}{2}
Take the square root of 6400.
x=40
Now solve the equation x=\frac{0±80}{2} when ± is plus. Divide 80 by 2.
x=-40
Now solve the equation x=\frac{0±80}{2} when ± is minus. Divide -80 by 2.
x=40 x=-40
The equation is now solved.
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