Skip to main content
Solve for x
Tick mark Image
Graph

Similar Problems from Web Search

Share

x^{2}=\frac{128}{2}
Divide both sides by 2.
x^{2}=64
Divide 128 by 2 to get 64.
x^{2}-64=0
Subtract 64 from both sides.
\left(x-8\right)\left(x+8\right)=0
Consider x^{2}-64. Rewrite x^{2}-64 as x^{2}-8^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=8 x=-8
To find equation solutions, solve x-8=0 and x+8=0.
x^{2}=\frac{128}{2}
Divide both sides by 2.
x^{2}=64
Divide 128 by 2 to get 64.
x=8 x=-8
Take the square root of both sides of the equation.
x^{2}=\frac{128}{2}
Divide both sides by 2.
x^{2}=64
Divide 128 by 2 to get 64.
x^{2}-64=0
Subtract 64 from both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-64\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -64 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-64\right)}}{2}
Square 0.
x=\frac{0±\sqrt{256}}{2}
Multiply -4 times -64.
x=\frac{0±16}{2}
Take the square root of 256.
x=8
Now solve the equation x=\frac{0±16}{2} when ± is plus. Divide 16 by 2.
x=-8
Now solve the equation x=\frac{0±16}{2} when ± is minus. Divide -16 by 2.
x=8 x=-8
The equation is now solved.