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