Solve for y
y=14
y=0
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y^{2}-14y=0
Swap sides so that all variable terms are on the left hand side.
y\left(y-14\right)=0
Factor out y.
y=0 y=14
To find equation solutions, solve y=0 and y-14=0.
y^{2}-14y=0
Swap sides so that all variable terms are on the left hand side.
y=\frac{-\left(-14\right)±\sqrt{\left(-14\right)^{2}}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -14 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-\left(-14\right)±14}{2}
Take the square root of \left(-14\right)^{2}.
y=\frac{14±14}{2}
The opposite of -14 is 14.
y=\frac{28}{2}
Now solve the equation y=\frac{14±14}{2} when ± is plus. Add 14 to 14.
y=14
Divide 28 by 2.
y=\frac{0}{2}
Now solve the equation y=\frac{14±14}{2} when ± is minus. Subtract 14 from 14.
y=0
Divide 0 by 2.
y=14 y=0
The equation is now solved.
y^{2}-14y=0
Swap sides so that all variable terms are on the left hand side.
y^{2}-14y+\left(-7\right)^{2}=\left(-7\right)^{2}
Divide -14, the coefficient of the x term, by 2 to get -7. Then add the square of -7 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
y^{2}-14y+49=49
Square -7.
\left(y-7\right)^{2}=49
Factor y^{2}-14y+49. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(y-7\right)^{2}}=\sqrt{49}
Take the square root of both sides of the equation.
y-7=7 y-7=-7
Simplify.
y=14 y=0
Add 7 to both sides of the equation.
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Simultaneous equation
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Limits
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