Solve for w
w = \frac{7}{4} = 1\frac{3}{4} = 1.75
w=0
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4w^{2}-7w=0
Subtract 7w from both sides.
w\left(4w-7\right)=0
Factor out w.
w=0 w=\frac{7}{4}
To find equation solutions, solve w=0 and 4w-7=0.
4w^{2}-7w=0
Subtract 7w from both sides.
w=\frac{-\left(-7\right)±\sqrt{\left(-7\right)^{2}}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -7 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
w=\frac{-\left(-7\right)±7}{2\times 4}
Take the square root of \left(-7\right)^{2}.
w=\frac{7±7}{2\times 4}
The opposite of -7 is 7.
w=\frac{7±7}{8}
Multiply 2 times 4.
w=\frac{14}{8}
Now solve the equation w=\frac{7±7}{8} when ± is plus. Add 7 to 7.
w=\frac{7}{4}
Reduce the fraction \frac{14}{8} to lowest terms by extracting and canceling out 2.
w=\frac{0}{8}
Now solve the equation w=\frac{7±7}{8} when ± is minus. Subtract 7 from 7.
w=0
Divide 0 by 8.
w=\frac{7}{4} w=0
The equation is now solved.
4w^{2}-7w=0
Subtract 7w from both sides.
\frac{4w^{2}-7w}{4}=\frac{0}{4}
Divide both sides by 4.
w^{2}-\frac{7}{4}w=\frac{0}{4}
Dividing by 4 undoes the multiplication by 4.
w^{2}-\frac{7}{4}w=0
Divide 0 by 4.
w^{2}-\frac{7}{4}w+\left(-\frac{7}{8}\right)^{2}=\left(-\frac{7}{8}\right)^{2}
Divide -\frac{7}{4}, the coefficient of the x term, by 2 to get -\frac{7}{8}. Then add the square of -\frac{7}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
w^{2}-\frac{7}{4}w+\frac{49}{64}=\frac{49}{64}
Square -\frac{7}{8} by squaring both the numerator and the denominator of the fraction.
\left(w-\frac{7}{8}\right)^{2}=\frac{49}{64}
Factor w^{2}-\frac{7}{4}w+\frac{49}{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(w-\frac{7}{8}\right)^{2}}=\sqrt{\frac{49}{64}}
Take the square root of both sides of the equation.
w-\frac{7}{8}=\frac{7}{8} w-\frac{7}{8}=-\frac{7}{8}
Simplify.
w=\frac{7}{4} w=0
Add \frac{7}{8} to both sides of the equation.
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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