Solve for w
w=-3
w=0
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4w^{2}+12w=0
Add 12w to both sides.
w\left(4w+12\right)=0
Factor out w.
w=0 w=-3
To find equation solutions, solve w=0 and 4w+12=0.
4w^{2}+12w=0
Add 12w to both sides.
w=\frac{-12±\sqrt{12^{2}}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, 12 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
w=\frac{-12±12}{2\times 4}
Take the square root of 12^{2}.
w=\frac{-12±12}{8}
Multiply 2 times 4.
w=\frac{0}{8}
Now solve the equation w=\frac{-12±12}{8} when ± is plus. Add -12 to 12.
w=0
Divide 0 by 8.
w=-\frac{24}{8}
Now solve the equation w=\frac{-12±12}{8} when ± is minus. Subtract 12 from -12.
w=-3
Divide -24 by 8.
w=0 w=-3
The equation is now solved.
4w^{2}+12w=0
Add 12w to both sides.
\frac{4w^{2}+12w}{4}=\frac{0}{4}
Divide both sides by 4.
w^{2}+\frac{12}{4}w=\frac{0}{4}
Dividing by 4 undoes the multiplication by 4.
w^{2}+3w=\frac{0}{4}
Divide 12 by 4.
w^{2}+3w=0
Divide 0 by 4.
w^{2}+3w+\left(\frac{3}{2}\right)^{2}=\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.
w^{2}+3w+\frac{9}{4}=\frac{9}{4}
Square \frac{3}{2} by squaring both the numerator and the denominator of the fraction.
\left(w+\frac{3}{2}\right)^{2}=\frac{9}{4}
Factor w^{2}+3w+\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(w+\frac{3}{2}\right)^{2}}=\sqrt{\frac{9}{4}}
Take the square root of both sides of the equation.
w+\frac{3}{2}=\frac{3}{2} w+\frac{3}{2}=-\frac{3}{2}
Simplify.
w=0 w=-3
Subtract \frac{3}{2} from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
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}