Solve for y
y=-3
y=2
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\left(y+5\right)y=\left(2y+3\right)\times 2
Variable y cannot be equal to any of the values -5,-\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(y+5\right)\left(2y+3\right), the least common multiple of 2y+3,y+5.
y^{2}+5y=\left(2y+3\right)\times 2
Use the distributive property to multiply y+5 by y.
y^{2}+5y=4y+6
Use the distributive property to multiply 2y+3 by 2.
y^{2}+5y-4y=6
Subtract 4y from both sides.
y^{2}+y=6
Combine 5y and -4y to get y.
y^{2}+y-6=0
Subtract 6 from both sides.
y=\frac{-1±\sqrt{1^{2}-4\left(-6\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{-1±\sqrt{1-4\left(-6\right)}}{2}
Square 1.
y=\frac{-1±\sqrt{1+24}}{2}
Multiply -4 times -6.
y=\frac{-1±\sqrt{25}}{2}
Add 1 to 24.
y=\frac{-1±5}{2}
Take the square root of 25.
y=\frac{4}{2}
Now solve the equation y=\frac{-1±5}{2} when ± is plus. Add -1 to 5.
y=2
Divide 4 by 2.
y=-\frac{6}{2}
Now solve the equation y=\frac{-1±5}{2} when ± is minus. Subtract 5 from -1.
y=-3
Divide -6 by 2.
y=2 y=-3
The equation is now solved.
\left(y+5\right)y=\left(2y+3\right)\times 2
Variable y cannot be equal to any of the values -5,-\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(y+5\right)\left(2y+3\right), the least common multiple of 2y+3,y+5.
y^{2}+5y=\left(2y+3\right)\times 2
Use the distributive property to multiply y+5 by y.
y^{2}+5y=4y+6
Use the distributive property to multiply 2y+3 by 2.
y^{2}+5y-4y=6
Subtract 4y from both sides.
y^{2}+y=6
Combine 5y and -4y to get y.
y^{2}+y+\left(\frac{1}{2}\right)^{2}=6+\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
y^{2}+y+\frac{1}{4}=6+\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
y^{2}+y+\frac{1}{4}=\frac{25}{4}
Add 6 to \frac{1}{4}.
\left(y+\frac{1}{2}\right)^{2}=\frac{25}{4}
Factor y^{2}+y+\frac{1}{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{1}{2}\right)^{2}}=\sqrt{\frac{25}{4}}
Take the square root of both sides of the equation.
y+\frac{1}{2}=\frac{5}{2} y+\frac{1}{2}=-\frac{5}{2}
Simplify.
y=2 y=-3
Subtract \frac{1}{2} from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
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y = 3x + 4
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699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}