Solve for P
P=8
P=-8
Share
Copied to clipboard
P^{2}-64=0
Subtract 64 from both sides.
\left(P-8\right)\left(P+8\right)=0
Consider P^{2}-64. Rewrite P^{2}-64 as P^{2}-8^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
P=8 P=-8
To find equation solutions, solve P-8=0 and P+8=0.
P=8 P=-8
Take the square root of both sides of the equation.
P^{2}-64=0
Subtract 64 from both sides.
P=\frac{0±\sqrt{0^{2}-4\left(-64\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -64 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
P=\frac{0±\sqrt{-4\left(-64\right)}}{2}
Square 0.
P=\frac{0±\sqrt{256}}{2}
Multiply -4 times -64.
P=\frac{0±16}{2}
Take the square root of 256.
P=8
Now solve the equation P=\frac{0±16}{2} when ± is plus. Divide 16 by 2.
P=-8
Now solve the equation P=\frac{0±16}{2} when ± is minus. Divide -16 by 2.
P=8 P=-8
The equation is now solved.
Examples
Quadratic equation
{ 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}