Solve for x
x = \frac{5}{4} = 1\frac{1}{4} = 1.25
x = -\frac{5}{4} = -1\frac{1}{4} = -1.25
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x^{2}=\frac{25}{16}
Divide both sides by 16.
x^{2}-\frac{25}{16}=0
Subtract \frac{25}{16} from both sides.
16x^{2}-25=0
Multiply both sides by 16.
\left(4x-5\right)\left(4x+5\right)=0
Consider 16x^{2}-25. Rewrite 16x^{2}-25 as \left(4x\right)^{2}-5^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=\frac{5}{4} x=-\frac{5}{4}
To find equation solutions, solve 4x-5=0 and 4x+5=0.
x^{2}=\frac{25}{16}
Divide both sides by 16.
x=\frac{5}{4} x=-\frac{5}{4}
Take the square root of both sides of the equation.
x^{2}=\frac{25}{16}
Divide both sides by 16.
x^{2}-\frac{25}{16}=0
Subtract \frac{25}{16} from both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-\frac{25}{16}\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -\frac{25}{16} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-\frac{25}{16}\right)}}{2}
Square 0.
x=\frac{0±\sqrt{\frac{25}{4}}}{2}
Multiply -4 times -\frac{25}{16}.
x=\frac{0±\frac{5}{2}}{2}
Take the square root of \frac{25}{4}.
x=\frac{5}{4}
Now solve the equation x=\frac{0±\frac{5}{2}}{2} when ± is plus.
x=-\frac{5}{4}
Now solve the equation x=\frac{0±\frac{5}{2}}{2} when ± is minus.
x=\frac{5}{4} x=-\frac{5}{4}
The equation is now solved.
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