Solve for y
y=4
y=-12
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\left(y+4\right)^{2}=\frac{-192}{-3}
Divide both sides by -3.
\left(y+4\right)^{2}=64
Divide -192 by -3 to get 64.
y^{2}+8y+16=64
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(y+4\right)^{2}.
y^{2}+8y+16-64=0
Subtract 64 from both sides.
y^{2}+8y-48=0
Subtract 64 from 16 to get -48.
a+b=8 ab=-48
To solve the equation, factor y^{2}+8y-48 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.
-1,48 -2,24 -3,16 -4,12 -6,8
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -48.
-1+48=47 -2+24=22 -3+16=13 -4+12=8 -6+8=2
Calculate the sum for each pair.
a=-4 b=12
The solution is the pair that gives sum 8.
\left(y-4\right)\left(y+12\right)
Rewrite factored expression \left(y+a\right)\left(y+b\right) using the obtained values.
y=4 y=-12
To find equation solutions, solve y-4=0 and y+12=0.
\left(y+4\right)^{2}=\frac{-192}{-3}
Divide both sides by -3.
\left(y+4\right)^{2}=64
Divide -192 by -3 to get 64.
y^{2}+8y+16=64
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(y+4\right)^{2}.
y^{2}+8y+16-64=0
Subtract 64 from both sides.
y^{2}+8y-48=0
Subtract 64 from 16 to get -48.
a+b=8 ab=1\left(-48\right)=-48
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as y^{2}+ay+by-48. To find a and b, set up a system to be solved.
-1,48 -2,24 -3,16 -4,12 -6,8
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -48.
-1+48=47 -2+24=22 -3+16=13 -4+12=8 -6+8=2
Calculate the sum for each pair.
a=-4 b=12
The solution is the pair that gives sum 8.
\left(y^{2}-4y\right)+\left(12y-48\right)
Rewrite y^{2}+8y-48 as \left(y^{2}-4y\right)+\left(12y-48\right).
y\left(y-4\right)+12\left(y-4\right)
Factor out y in the first and 12 in the second group.
\left(y-4\right)\left(y+12\right)
Factor out common term y-4 by using distributive property.
y=4 y=-12
To find equation solutions, solve y-4=0 and y+12=0.
\left(y+4\right)^{2}=\frac{-192}{-3}
Divide both sides by -3.
\left(y+4\right)^{2}=64
Divide -192 by -3 to get 64.
y^{2}+8y+16=64
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(y+4\right)^{2}.
y^{2}+8y+16-64=0
Subtract 64 from both sides.
y^{2}+8y-48=0
Subtract 64 from 16 to get -48.
y=\frac{-8±\sqrt{8^{2}-4\left(-48\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 8 for b, and -48 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-8±\sqrt{64-4\left(-48\right)}}{2}
Square 8.
y=\frac{-8±\sqrt{64+192}}{2}
Multiply -4 times -48.
y=\frac{-8±\sqrt{256}}{2}
Add 64 to 192.
y=\frac{-8±16}{2}
Take the square root of 256.
y=\frac{8}{2}
Now solve the equation y=\frac{-8±16}{2} when ± is plus. Add -8 to 16.
y=4
Divide 8 by 2.
y=-\frac{24}{2}
Now solve the equation y=\frac{-8±16}{2} when ± is minus. Subtract 16 from -8.
y=-12
Divide -24 by 2.
y=4 y=-12
The equation is now solved.
\left(y+4\right)^{2}=\frac{-192}{-3}
Divide both sides by -3.
\left(y+4\right)^{2}=64
Divide -192 by -3 to get 64.
\sqrt{\left(y+4\right)^{2}}=\sqrt{64}
Take the square root of both sides of the equation.
y+4=8 y+4=-8
Simplify.
y=4 y=-12
Subtract 4 from both sides of the equation.
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