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-27+\left(4y+1\right)\times 5=y\left(4y+1\right)
Variable y cannot be equal to -\frac{1}{4} since division by zero is not defined. Multiply both sides of the equation by 4y+1.
-27+20y+5=y\left(4y+1\right)
Use the distributive property to multiply 4y+1 by 5.
-22+20y=y\left(4y+1\right)
Add -27 and 5 to get -22.
-22+20y=4y^{2}+y
Use the distributive property to multiply y by 4y+1.
-22+20y-4y^{2}=y
Subtract 4y^{2} from both sides.
-22+20y-4y^{2}-y=0
Subtract y from both sides.
-22+19y-4y^{2}=0
Combine 20y and -y to get 19y.
-4y^{2}+19y-22=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=19 ab=-4\left(-22\right)=88
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -4y^{2}+ay+by-22. To find a and b, set up a system to be solved.
1,88 2,44 4,22 8,11
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 88.
1+88=89 2+44=46 4+22=26 8+11=19
Calculate the sum for each pair.
a=11 b=8
The solution is the pair that gives sum 19.
\left(-4y^{2}+11y\right)+\left(8y-22\right)
Rewrite -4y^{2}+19y-22 as \left(-4y^{2}+11y\right)+\left(8y-22\right).
-y\left(4y-11\right)+2\left(4y-11\right)
Factor out -y in the first and 2 in the second group.
\left(4y-11\right)\left(-y+2\right)
Factor out common term 4y-11 by using distributive property.
y=\frac{11}{4} y=2
To find equation solutions, solve 4y-11=0 and -y+2=0.
-27+\left(4y+1\right)\times 5=y\left(4y+1\right)
Variable y cannot be equal to -\frac{1}{4} since division by zero is not defined. Multiply both sides of the equation by 4y+1.
-27+20y+5=y\left(4y+1\right)
Use the distributive property to multiply 4y+1 by 5.
-22+20y=y\left(4y+1\right)
Add -27 and 5 to get -22.
-22+20y=4y^{2}+y
Use the distributive property to multiply y by 4y+1.
-22+20y-4y^{2}=y
Subtract 4y^{2} from both sides.
-22+20y-4y^{2}-y=0
Subtract y from both sides.
-22+19y-4y^{2}=0
Combine 20y and -y to get 19y.
-4y^{2}+19y-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{-19±\sqrt{19^{2}-4\left(-4\right)\left(-22\right)}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, 19 for b, and -22 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-19±\sqrt{361-4\left(-4\right)\left(-22\right)}}{2\left(-4\right)}
Square 19.
y=\frac{-19±\sqrt{361+16\left(-22\right)}}{2\left(-4\right)}
Multiply -4 times -4.
y=\frac{-19±\sqrt{361-352}}{2\left(-4\right)}
Multiply 16 times -22.
y=\frac{-19±\sqrt{9}}{2\left(-4\right)}
Add 361 to -352.
y=\frac{-19±3}{2\left(-4\right)}
Take the square root of 9.
y=\frac{-19±3}{-8}
Multiply 2 times -4.
y=-\frac{16}{-8}
Now solve the equation y=\frac{-19±3}{-8} when ± is plus. Add -19 to 3.
y=2
Divide -16 by -8.
y=-\frac{22}{-8}
Now solve the equation y=\frac{-19±3}{-8} when ± is minus. Subtract 3 from -19.
y=\frac{11}{4}
Reduce the fraction \frac{-22}{-8} to lowest terms by extracting and canceling out 2.
y=2 y=\frac{11}{4}
The equation is now solved.
-27+\left(4y+1\right)\times 5=y\left(4y+1\right)
Variable y cannot be equal to -\frac{1}{4} since division by zero is not defined. Multiply both sides of the equation by 4y+1.
-27+20y+5=y\left(4y+1\right)
Use the distributive property to multiply 4y+1 by 5.
-22+20y=y\left(4y+1\right)
Add -27 and 5 to get -22.
-22+20y=4y^{2}+y
Use the distributive property to multiply y by 4y+1.
-22+20y-4y^{2}=y
Subtract 4y^{2} from both sides.
-22+20y-4y^{2}-y=0
Subtract y from both sides.
-22+19y-4y^{2}=0
Combine 20y and -y to get 19y.
19y-4y^{2}=22
Add 22 to both sides. Anything plus zero gives itself.
-4y^{2}+19y=22
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.
\frac{-4y^{2}+19y}{-4}=\frac{22}{-4}
Divide both sides by -4.
y^{2}+\frac{19}{-4}y=\frac{22}{-4}
Dividing by -4 undoes the multiplication by -4.
y^{2}-\frac{19}{4}y=\frac{22}{-4}
Divide 19 by -4.
y^{2}-\frac{19}{4}y=-\frac{11}{2}
Reduce the fraction \frac{22}{-4} to lowest terms by extracting and canceling out 2.
y^{2}-\frac{19}{4}y+\left(-\frac{19}{8}\right)^{2}=-\frac{11}{2}+\left(-\frac{19}{8}\right)^{2}
Divide -\frac{19}{4}, the coefficient of the x term, by 2 to get -\frac{19}{8}. Then add the square of -\frac{19}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
y^{2}-\frac{19}{4}y+\frac{361}{64}=-\frac{11}{2}+\frac{361}{64}
Square -\frac{19}{8} by squaring both the numerator and the denominator of the fraction.
y^{2}-\frac{19}{4}y+\frac{361}{64}=\frac{9}{64}
Add -\frac{11}{2} to \frac{361}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(y-\frac{19}{8}\right)^{2}=\frac{9}{64}
Factor y^{2}-\frac{19}{4}y+\frac{361}{64}. 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{19}{8}\right)^{2}}=\sqrt{\frac{9}{64}}
Take the square root of both sides of the equation.
y-\frac{19}{8}=\frac{3}{8} y-\frac{19}{8}=-\frac{3}{8}
Simplify.
y=\frac{11}{4} y=2
Add \frac{19}{8} to both sides of the equation.