Solve for x
x=400
x=-400
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x^{2}=10\times 10^{5}\times 0.16
Multiply 2 and 5 to get 10.
x^{2}=10\times 100000\times 0.16
Calculate 10 to the power of 5 and get 100000.
x^{2}=1000000\times 0.16
Multiply 10 and 100000 to get 1000000.
x^{2}=160000
Multiply 1000000 and 0.16 to get 160000.
x^{2}-160000=0
Subtract 160000 from both sides.
\left(x-400\right)\left(x+400\right)=0
Consider x^{2}-160000. Rewrite x^{2}-160000 as x^{2}-400^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=400 x=-400
To find equation solutions, solve x-400=0 and x+400=0.
x^{2}=10\times 10^{5}\times 0.16
Multiply 2 and 5 to get 10.
x^{2}=10\times 100000\times 0.16
Calculate 10 to the power of 5 and get 100000.
x^{2}=1000000\times 0.16
Multiply 10 and 100000 to get 1000000.
x^{2}=160000
Multiply 1000000 and 0.16 to get 160000.
x=400 x=-400
Take the square root of both sides of the equation.
x^{2}=10\times 10^{5}\times 0.16
Multiply 2 and 5 to get 10.
x^{2}=10\times 100000\times 0.16
Calculate 10 to the power of 5 and get 100000.
x^{2}=1000000\times 0.16
Multiply 10 and 100000 to get 1000000.
x^{2}=160000
Multiply 1000000 and 0.16 to get 160000.
x^{2}-160000=0
Subtract 160000 from both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-160000\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -160000 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-160000\right)}}{2}
Square 0.
x=\frac{0±\sqrt{640000}}{2}
Multiply -4 times -160000.
x=\frac{0±800}{2}
Take the square root of 640000.
x=400
Now solve the equation x=\frac{0±800}{2} when ± is plus. Divide 800 by 2.
x=-400
Now solve the equation x=\frac{0±800}{2} when ± is minus. Divide -800 by 2.
x=400 x=-400
The equation is now solved.
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