Solve for y
y=-11
y=-2
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yy+22=-13y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}+22=-13y
Multiply y and y to get y^{2}.
y^{2}+22+13y=0
Add 13y to both sides.
y^{2}+13y+22=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=13 ab=22
To solve the equation, factor y^{2}+13y+22 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.
1,22 2,11
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 22.
1+22=23 2+11=13
Calculate the sum for each pair.
a=2 b=11
The solution is the pair that gives sum 13.
\left(y+2\right)\left(y+11\right)
Rewrite factored expression \left(y+a\right)\left(y+b\right) using the obtained values.
y=-2 y=-11
To find equation solutions, solve y+2=0 and y+11=0.
yy+22=-13y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}+22=-13y
Multiply y and y to get y^{2}.
y^{2}+22+13y=0
Add 13y to both sides.
y^{2}+13y+22=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=13 ab=1\times 22=22
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as y^{2}+ay+by+22. To find a and b, set up a system to be solved.
1,22 2,11
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 22.
1+22=23 2+11=13
Calculate the sum for each pair.
a=2 b=11
The solution is the pair that gives sum 13.
\left(y^{2}+2y\right)+\left(11y+22\right)
Rewrite y^{2}+13y+22 as \left(y^{2}+2y\right)+\left(11y+22\right).
y\left(y+2\right)+11\left(y+2\right)
Factor out y in the first and 11 in the second group.
\left(y+2\right)\left(y+11\right)
Factor out common term y+2 by using distributive property.
y=-2 y=-11
To find equation solutions, solve y+2=0 and y+11=0.
yy+22=-13y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}+22=-13y
Multiply y and y to get y^{2}.
y^{2}+22+13y=0
Add 13y to both sides.
y^{2}+13y+22=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{-13±\sqrt{13^{2}-4\times 22}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 13 for b, and 22 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-13±\sqrt{169-4\times 22}}{2}
Square 13.
y=\frac{-13±\sqrt{169-88}}{2}
Multiply -4 times 22.
y=\frac{-13±\sqrt{81}}{2}
Add 169 to -88.
y=\frac{-13±9}{2}
Take the square root of 81.
y=-\frac{4}{2}
Now solve the equation y=\frac{-13±9}{2} when ± is plus. Add -13 to 9.
y=-2
Divide -4 by 2.
y=-\frac{22}{2}
Now solve the equation y=\frac{-13±9}{2} when ± is minus. Subtract 9 from -13.
y=-11
Divide -22 by 2.
y=-2 y=-11
The equation is now solved.
yy+22=-13y
Variable y cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by y.
y^{2}+22=-13y
Multiply y and y to get y^{2}.
y^{2}+22+13y=0
Add 13y to both sides.
y^{2}+13y=-22
Subtract 22 from both sides. Anything subtracted from zero gives its negation.
y^{2}+13y+\left(\frac{13}{2}\right)^{2}=-22+\left(\frac{13}{2}\right)^{2}
Divide 13, the coefficient of the x term, by 2 to get \frac{13}{2}. Then add the square of \frac{13}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
y^{2}+13y+\frac{169}{4}=-22+\frac{169}{4}
Square \frac{13}{2} by squaring both the numerator and the denominator of the fraction.
y^{2}+13y+\frac{169}{4}=\frac{81}{4}
Add -22 to \frac{169}{4}.
\left(y+\frac{13}{2}\right)^{2}=\frac{81}{4}
Factor y^{2}+13y+\frac{169}{4}. 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+\frac{13}{2}\right)^{2}}=\sqrt{\frac{81}{4}}
Take the square root of both sides of the equation.
y+\frac{13}{2}=\frac{9}{2} y+\frac{13}{2}=-\frac{9}{2}
Simplify.
y=-2 y=-11
Subtract \frac{13}{2} from both sides of the equation.
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Limits
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