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y+2+y^{2}=4y+6
Subtract 1 from 3 to get 2.
y+2+y^{2}-4y=6
Subtract 4y from both sides.
-3y+2+y^{2}=6
Combine y and -4y to get -3y.
-3y+2+y^{2}-6=0
Subtract 6 from both sides.
-3y-4+y^{2}=0
Subtract 6 from 2 to get -4.
y^{2}-3y-4=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-3 ab=-4
To solve the equation, factor y^{2}-3y-4 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,-4 2,-2
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. List all such integer pairs that give product -4.
1-4=-3 2-2=0
Calculate the sum for each pair.
a=-4 b=1
The solution is the pair that gives sum -3.
\left(y-4\right)\left(y+1\right)
Rewrite factored expression \left(y+a\right)\left(y+b\right) using the obtained values.
y=4 y=-1
To find equation solutions, solve y-4=0 and y+1=0.
y+2+y^{2}=4y+6
Subtract 1 from 3 to get 2.
y+2+y^{2}-4y=6
Subtract 4y from both sides.
-3y+2+y^{2}=6
Combine y and -4y to get -3y.
-3y+2+y^{2}-6=0
Subtract 6 from both sides.
-3y-4+y^{2}=0
Subtract 6 from 2 to get -4.
y^{2}-3y-4=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-3 ab=1\left(-4\right)=-4
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as y^{2}+ay+by-4. To find a and b, set up a system to be solved.
1,-4 2,-2
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. List all such integer pairs that give product -4.
1-4=-3 2-2=0
Calculate the sum for each pair.
a=-4 b=1
The solution is the pair that gives sum -3.
\left(y^{2}-4y\right)+\left(y-4\right)
Rewrite y^{2}-3y-4 as \left(y^{2}-4y\right)+\left(y-4\right).
y\left(y-4\right)+y-4
Factor out y in y^{2}-4y.
\left(y-4\right)\left(y+1\right)
Factor out common term y-4 by using distributive property.
y=4 y=-1
To find equation solutions, solve y-4=0 and y+1=0.
y+2+y^{2}=4y+6
Subtract 1 from 3 to get 2.
y+2+y^{2}-4y=6
Subtract 4y from both sides.
-3y+2+y^{2}=6
Combine y and -4y to get -3y.
-3y+2+y^{2}-6=0
Subtract 6 from both sides.
-3y-4+y^{2}=0
Subtract 6 from 2 to get -4.
y^{2}-3y-4=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(-3\right)±\sqrt{\left(-3\right)^{2}-4\left(-4\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -3 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-\left(-3\right)±\sqrt{9-4\left(-4\right)}}{2}
Square -3.
y=\frac{-\left(-3\right)±\sqrt{9+16}}{2}
Multiply -4 times -4.
y=\frac{-\left(-3\right)±\sqrt{25}}{2}
Add 9 to 16.
y=\frac{-\left(-3\right)±5}{2}
Take the square root of 25.
y=\frac{3±5}{2}
The opposite of -3 is 3.
y=\frac{8}{2}
Now solve the equation y=\frac{3±5}{2} when ± is plus. Add 3 to 5.
y=4
Divide 8 by 2.
y=-\frac{2}{2}
Now solve the equation y=\frac{3±5}{2} when ± is minus. Subtract 5 from 3.
y=-1
Divide -2 by 2.
y=4 y=-1
The equation is now solved.
y+2+y^{2}=4y+6
Subtract 1 from 3 to get 2.
y+2+y^{2}-4y=6
Subtract 4y from both sides.
-3y+2+y^{2}=6
Combine y and -4y to get -3y.
-3y+y^{2}=6-2
Subtract 2 from both sides.
-3y+y^{2}=4
Subtract 2 from 6 to get 4.
y^{2}-3y=4
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
y^{2}-3y+\left(-\frac{3}{2}\right)^{2}=4+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
y^{2}-3y+\frac{9}{4}=4+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
y^{2}-3y+\frac{9}{4}=\frac{25}{4}
Add 4 to \frac{9}{4}.
\left(y-\frac{3}{2}\right)^{2}=\frac{25}{4}
Factor y^{2}-3y+\frac{9}{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{3}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
y-\frac{3}{2}=\frac{5}{2} y-\frac{3}{2}=-\frac{5}{2}
Simplify.
y=4 y=-1
Add \frac{3}{2} to both sides of the equation.