Solve for p
p=1
p=7
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p-2+5p-5=p\left(p-2\right)
Variable p cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by p\left(p-2\right), the least common multiple of p,p^{2}-2p.
6p-2-5=p\left(p-2\right)
Combine p and 5p to get 6p.
6p-7=p\left(p-2\right)
Subtract 5 from -2 to get -7.
6p-7=p^{2}-2p
Use the distributive property to multiply p by p-2.
6p-7-p^{2}=-2p
Subtract p^{2} from both sides.
6p-7-p^{2}+2p=0
Add 2p to both sides.
8p-7-p^{2}=0
Combine 6p and 2p to get 8p.
-p^{2}+8p-7=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=8 ab=-\left(-7\right)=7
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -p^{2}+ap+bp-7. To find a and b, set up a system to be solved.
a=7 b=1
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(-p^{2}+7p\right)+\left(p-7\right)
Rewrite -p^{2}+8p-7 as \left(-p^{2}+7p\right)+\left(p-7\right).
-p\left(p-7\right)+p-7
Factor out -p in -p^{2}+7p.
\left(p-7\right)\left(-p+1\right)
Factor out common term p-7 by using distributive property.
p=7 p=1
To find equation solutions, solve p-7=0 and -p+1=0.
p-2+5p-5=p\left(p-2\right)
Variable p cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by p\left(p-2\right), the least common multiple of p,p^{2}-2p.
6p-2-5=p\left(p-2\right)
Combine p and 5p to get 6p.
6p-7=p\left(p-2\right)
Subtract 5 from -2 to get -7.
6p-7=p^{2}-2p
Use the distributive property to multiply p by p-2.
6p-7-p^{2}=-2p
Subtract p^{2} from both sides.
6p-7-p^{2}+2p=0
Add 2p to both sides.
8p-7-p^{2}=0
Combine 6p and 2p to get 8p.
-p^{2}+8p-7=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.
p=\frac{-8±\sqrt{8^{2}-4\left(-1\right)\left(-7\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 8 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
p=\frac{-8±\sqrt{64-4\left(-1\right)\left(-7\right)}}{2\left(-1\right)}
Square 8.
p=\frac{-8±\sqrt{64+4\left(-7\right)}}{2\left(-1\right)}
Multiply -4 times -1.
p=\frac{-8±\sqrt{64-28}}{2\left(-1\right)}
Multiply 4 times -7.
p=\frac{-8±\sqrt{36}}{2\left(-1\right)}
Add 64 to -28.
p=\frac{-8±6}{2\left(-1\right)}
Take the square root of 36.
p=\frac{-8±6}{-2}
Multiply 2 times -1.
p=-\frac{2}{-2}
Now solve the equation p=\frac{-8±6}{-2} when ± is plus. Add -8 to 6.
p=1
Divide -2 by -2.
p=-\frac{14}{-2}
Now solve the equation p=\frac{-8±6}{-2} when ± is minus. Subtract 6 from -8.
p=7
Divide -14 by -2.
p=1 p=7
The equation is now solved.
p-2+5p-5=p\left(p-2\right)
Variable p cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by p\left(p-2\right), the least common multiple of p,p^{2}-2p.
6p-2-5=p\left(p-2\right)
Combine p and 5p to get 6p.
6p-7=p\left(p-2\right)
Subtract 5 from -2 to get -7.
6p-7=p^{2}-2p
Use the distributive property to multiply p by p-2.
6p-7-p^{2}=-2p
Subtract p^{2} from both sides.
6p-7-p^{2}+2p=0
Add 2p to both sides.
8p-7-p^{2}=0
Combine 6p and 2p to get 8p.
8p-p^{2}=7
Add 7 to both sides. Anything plus zero gives itself.
-p^{2}+8p=7
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{-p^{2}+8p}{-1}=\frac{7}{-1}
Divide both sides by -1.
p^{2}+\frac{8}{-1}p=\frac{7}{-1}
Dividing by -1 undoes the multiplication by -1.
p^{2}-8p=\frac{7}{-1}
Divide 8 by -1.
p^{2}-8p=-7
Divide 7 by -1.
p^{2}-8p+\left(-4\right)^{2}=-7+\left(-4\right)^{2}
Divide -8, the coefficient of the x term, by 2 to get -4. Then add the square of -4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
p^{2}-8p+16=-7+16
Square -4.
p^{2}-8p+16=9
Add -7 to 16.
\left(p-4\right)^{2}=9
Factor p^{2}-8p+16. 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-4\right)^{2}}=\sqrt{9}
Take the square root of both sides of the equation.
p-4=3 p-4=-3
Simplify.
p=7 p=1
Add 4 to 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}