Solve for x
x=1
x=-1
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x^{2}-1=0
Divide both sides by 16.
\left(x-1\right)\left(x+1\right)=0
Consider x^{2}-1. Rewrite x^{2}-1 as x^{2}-1^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=1 x=-1
To find equation solutions, solve x-1=0 and x+1=0.
16x^{2}=16
Add 16 to both sides. Anything plus zero gives itself.
x^{2}=\frac{16}{16}
Divide both sides by 16.
x^{2}=1
Divide 16 by 16 to get 1.
x=1 x=-1
Take the square root of both sides of the equation.
16x^{2}-16=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times 16\left(-16\right)}}{2\times 16}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 16 for a, 0 for b, and -16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 16\left(-16\right)}}{2\times 16}
Square 0.
x=\frac{0±\sqrt{-64\left(-16\right)}}{2\times 16}
Multiply -4 times 16.
x=\frac{0±\sqrt{1024}}{2\times 16}
Multiply -64 times -16.
x=\frac{0±32}{2\times 16}
Take the square root of 1024.
x=\frac{0±32}{32}
Multiply 2 times 16.
x=1
Now solve the equation x=\frac{0±32}{32} when ± is plus. Divide 32 by 32.
x=-1
Now solve the equation x=\frac{0±32}{32} when ± is minus. Divide -32 by 32.
x=1 x=-1
The equation is now solved.
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