Solve for y
y=9
y=-9
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yy=3\times 27
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3y, the least common multiple of 3,y.
y^{2}=3\times 27
Multiply y and y to get y^{2}.
y^{2}=81
Multiply 3 and 27 to get 81.
y=9 y=-9
Take the square root of both sides of the equation.
yy=3\times 27
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3y, the least common multiple of 3,y.
y^{2}=3\times 27
Multiply y and y to get y^{2}.
y^{2}=81
Multiply 3 and 27 to get 81.
y^{2}-81=0
Subtract 81 from both sides.
y=\frac{0±\sqrt{0^{2}-4\left(-81\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -81 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{0±\sqrt{-4\left(-81\right)}}{2}
Square 0.
y=\frac{0±\sqrt{324}}{2}
Multiply -4 times -81.
y=\frac{0±18}{2}
Take the square root of 324.
y=9
Now solve the equation y=\frac{0±18}{2} when ± is plus. Divide 18 by 2.
y=-9
Now solve the equation y=\frac{0±18}{2} when ± is minus. Divide -18 by 2.
y=9 y=-9
The equation is now solved.
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