Solve for x
x=20\sqrt{5}\approx 44.72135955
x=-20\sqrt{5}\approx -44.72135955
Graph
Share
Copied to clipboard
50=\frac{1}{40}x^{2}
Multiply \frac{1}{2} and 0.05 to get \frac{1}{40}.
\frac{1}{40}x^{2}=50
Swap sides so that all variable terms are on the left hand side.
x^{2}=50\times 40
Multiply both sides by 40, the reciprocal of \frac{1}{40}.
x^{2}=2000
Multiply 50 and 40 to get 2000.
x=20\sqrt{5} x=-20\sqrt{5}
Take the square root of both sides of the equation.
50=\frac{1}{40}x^{2}
Multiply \frac{1}{2} and 0.05 to get \frac{1}{40}.
\frac{1}{40}x^{2}=50
Swap sides so that all variable terms are on the left hand side.
\frac{1}{40}x^{2}-50=0
Subtract 50 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times \frac{1}{40}\left(-50\right)}}{2\times \frac{1}{40}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{40} for a, 0 for b, and -50 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{1}{40}\left(-50\right)}}{2\times \frac{1}{40}}
Square 0.
x=\frac{0±\sqrt{-\frac{1}{10}\left(-50\right)}}{2\times \frac{1}{40}}
Multiply -4 times \frac{1}{40}.
x=\frac{0±\sqrt{5}}{2\times \frac{1}{40}}
Multiply -\frac{1}{10} times -50.
x=\frac{0±\sqrt{5}}{\frac{1}{20}}
Multiply 2 times \frac{1}{40}.
x=20\sqrt{5}
Now solve the equation x=\frac{0±\sqrt{5}}{\frac{1}{20}} when ± is plus.
x=-20\sqrt{5}
Now solve the equation x=\frac{0±\sqrt{5}}{\frac{1}{20}} when ± is minus.
x=20\sqrt{5} x=-20\sqrt{5}
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}