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yy-3=2y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}-3=2y
Multiply y and y to get y^{2}.
y^{2}-3-2y=0
Subtract 2y from both sides.
y^{2}-2y-3=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-2 ab=-3
To solve the equation, factor y^{2}-2y-3 using formula y^{2}+\left(a+b\right)y+ab=\left(y+a\right)\left(y+b\right). To find a and b, set up a system to be solved.
a=-3 b=1
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. The only such pair is the system solution.
\left(y-3\right)\left(y+1\right)
Rewrite factored expression \left(y+a\right)\left(y+b\right) using the obtained values.
y=3 y=-1
To find equation solutions, solve y-3=0 and y+1=0.
yy-3=2y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}-3=2y
Multiply y and y to get y^{2}.
y^{2}-3-2y=0
Subtract 2y from both sides.
y^{2}-2y-3=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-2 ab=1\left(-3\right)=-3
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as y^{2}+ay+by-3. To find a and b, set up a system to be solved.
a=-3 b=1
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. The only such pair is the system solution.
\left(y^{2}-3y\right)+\left(y-3\right)
Rewrite y^{2}-2y-3 as \left(y^{2}-3y\right)+\left(y-3\right).
y\left(y-3\right)+y-3
Factor out y in y^{2}-3y.
\left(y-3\right)\left(y+1\right)
Factor out common term y-3 by using distributive property.
y=3 y=-1
To find equation solutions, solve y-3=0 and y+1=0.
yy-3=2y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}-3=2y
Multiply y and y to get y^{2}.
y^{2}-3-2y=0
Subtract 2y from both sides.
y^{2}-2y-3=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
y=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-3\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and -3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-\left(-2\right)±\sqrt{4-4\left(-3\right)}}{2}
Square -2.
y=\frac{-\left(-2\right)±\sqrt{4+12}}{2}
Multiply -4 times -3.
y=\frac{-\left(-2\right)±\sqrt{16}}{2}
Add 4 to 12.
y=\frac{-\left(-2\right)±4}{2}
Take the square root of 16.
y=\frac{2±4}{2}
The opposite of -2 is 2.
y=\frac{6}{2}
Now solve the equation y=\frac{2±4}{2} when ± is plus. Add 2 to 4.
y=3
Divide 6 by 2.
y=-\frac{2}{2}
Now solve the equation y=\frac{2±4}{2} when ± is minus. Subtract 4 from 2.
y=-1
Divide -2 by 2.
y=3 y=-1
The equation is now solved.
yy-3=2y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}-3=2y
Multiply y and y to get y^{2}.
y^{2}-3-2y=0
Subtract 2y from both sides.
y^{2}-2y=3
Add 3 to both sides. Anything plus zero gives itself.
y^{2}-2y+1=3+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
y^{2}-2y+1=4
Add 3 to 1.
\left(y-1\right)^{2}=4
Factor y^{2}-2y+1. 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-1\right)^{2}}=\sqrt{4}
Take the square root of both sides of the equation.
y-1=2 y-1=-2
Simplify.
y=3 y=-1
Add 1 to both sides of the equation.