Solve for y
y=-2
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y\left(y+6\right)-\left(y-4\right)=y
Variable y cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by y\left(y-1\right), the least common multiple of y-1,y^{2}-y.
y^{2}+6y-\left(y-4\right)=y
Use the distributive property to multiply y by y+6.
y^{2}+6y-y+4=y
To find the opposite of y-4, find the opposite of each term.
y^{2}+5y+4=y
Combine 6y and -y to get 5y.
y^{2}+5y+4-y=0
Subtract y from both sides.
y^{2}+4y+4=0
Combine 5y and -y to get 4y.
a+b=4 ab=4
To solve the equation, factor y^{2}+4y+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 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 4.
1+4=5 2+2=4
Calculate the sum for each pair.
a=2 b=2
The solution is the pair that gives sum 4.
\left(y+2\right)\left(y+2\right)
Rewrite factored expression \left(y+a\right)\left(y+b\right) using the obtained values.
\left(y+2\right)^{2}
Rewrite as a binomial square.
y=-2
To find equation solution, solve y+2=0.
y\left(y+6\right)-\left(y-4\right)=y
Variable y cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by y\left(y-1\right), the least common multiple of y-1,y^{2}-y.
y^{2}+6y-\left(y-4\right)=y
Use the distributive property to multiply y by y+6.
y^{2}+6y-y+4=y
To find the opposite of y-4, find the opposite of each term.
y^{2}+5y+4=y
Combine 6y and -y to get 5y.
y^{2}+5y+4-y=0
Subtract y from both sides.
y^{2}+4y+4=0
Combine 5y and -y to get 4y.
a+b=4 ab=1\times 4=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 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 4.
1+4=5 2+2=4
Calculate the sum for each pair.
a=2 b=2
The solution is the pair that gives sum 4.
\left(y^{2}+2y\right)+\left(2y+4\right)
Rewrite y^{2}+4y+4 as \left(y^{2}+2y\right)+\left(2y+4\right).
y\left(y+2\right)+2\left(y+2\right)
Factor out y in the first and 2 in the second group.
\left(y+2\right)\left(y+2\right)
Factor out common term y+2 by using distributive property.
\left(y+2\right)^{2}
Rewrite as a binomial square.
y=-2
To find equation solution, solve y+2=0.
y\left(y+6\right)-\left(y-4\right)=y
Variable y cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by y\left(y-1\right), the least common multiple of y-1,y^{2}-y.
y^{2}+6y-\left(y-4\right)=y
Use the distributive property to multiply y by y+6.
y^{2}+6y-y+4=y
To find the opposite of y-4, find the opposite of each term.
y^{2}+5y+4=y
Combine 6y and -y to get 5y.
y^{2}+5y+4-y=0
Subtract y from both sides.
y^{2}+4y+4=0
Combine 5y and -y to get 4y.
y=\frac{-4±\sqrt{4^{2}-4\times 4}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 4 for b, and 4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-4±\sqrt{16-4\times 4}}{2}
Square 4.
y=\frac{-4±\sqrt{16-16}}{2}
Multiply -4 times 4.
y=\frac{-4±\sqrt{0}}{2}
Add 16 to -16.
y=-\frac{4}{2}
Take the square root of 0.
y=-2
Divide -4 by 2.
y\left(y+6\right)-\left(y-4\right)=y
Variable y cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by y\left(y-1\right), the least common multiple of y-1,y^{2}-y.
y^{2}+6y-\left(y-4\right)=y
Use the distributive property to multiply y by y+6.
y^{2}+6y-y+4=y
To find the opposite of y-4, find the opposite of each term.
y^{2}+5y+4=y
Combine 6y and -y to get 5y.
y^{2}+5y+4-y=0
Subtract y from both sides.
y^{2}+4y+4=0
Combine 5y and -y to get 4y.
\left(y+2\right)^{2}=0
Factor y^{2}+4y+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+2\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
y+2=0 y+2=0
Simplify.
y=-2 y=-2
Subtract 2 from both sides of the equation.
y=-2
The equation is now solved. Solutions are the same.
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Simultaneous equation
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Differentiation
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Integration
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Limits
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