Solve for p
p=7
p=0
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5p^{2}-35p=0
Subtract 35p from both sides.
p\left(5p-35\right)=0
Factor out p.
p=0 p=7
To find equation solutions, solve p=0 and 5p-35=0.
5p^{2}-35p=0
Subtract 35p from both sides.
p=\frac{-\left(-35\right)±\sqrt{\left(-35\right)^{2}}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, -35 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
p=\frac{-\left(-35\right)±35}{2\times 5}
Take the square root of \left(-35\right)^{2}.
p=\frac{35±35}{2\times 5}
The opposite of -35 is 35.
p=\frac{35±35}{10}
Multiply 2 times 5.
p=\frac{70}{10}
Now solve the equation p=\frac{35±35}{10} when ± is plus. Add 35 to 35.
p=7
Divide 70 by 10.
p=\frac{0}{10}
Now solve the equation p=\frac{35±35}{10} when ± is minus. Subtract 35 from 35.
p=0
Divide 0 by 10.
p=7 p=0
The equation is now solved.
5p^{2}-35p=0
Subtract 35p from both sides.
\frac{5p^{2}-35p}{5}=\frac{0}{5}
Divide both sides by 5.
p^{2}+\left(-\frac{35}{5}\right)p=\frac{0}{5}
Dividing by 5 undoes the multiplication by 5.
p^{2}-7p=\frac{0}{5}
Divide -35 by 5.
p^{2}-7p=0
Divide 0 by 5.
p^{2}-7p+\left(-\frac{7}{2}\right)^{2}=\left(-\frac{7}{2}\right)^{2}
Divide -7, the coefficient of the x term, by 2 to get -\frac{7}{2}. Then add the square of -\frac{7}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
p^{2}-7p+\frac{49}{4}=\frac{49}{4}
Square -\frac{7}{2} by squaring both the numerator and the denominator of the fraction.
\left(p-\frac{7}{2}\right)^{2}=\frac{49}{4}
Factor p^{2}-7p+\frac{49}{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(p-\frac{7}{2}\right)^{2}}=\sqrt{\frac{49}{4}}
Take the square root of both sides of the equation.
p-\frac{7}{2}=\frac{7}{2} p-\frac{7}{2}=-\frac{7}{2}
Simplify.
p=7 p=0
Add \frac{7}{2} 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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