Solve for x
x=8
Graph
Share
Copied to clipboard
\frac{1}{2}x+5-3x=-15
Subtract 3x from both sides.
-\frac{5}{2}x+5=-15
Combine \frac{1}{2}x and -3x to get -\frac{5}{2}x.
-\frac{5}{2}x=-15-5
Subtract 5 from both sides.
-\frac{5}{2}x=-20
Subtract 5 from -15 to get -20.
x=-20\left(-\frac{2}{5}\right)
Multiply both sides by -\frac{2}{5}, the reciprocal of -\frac{5}{2}.
x=\frac{-20\left(-2\right)}{5}
Express -20\left(-\frac{2}{5}\right) as a single fraction.
x=\frac{40}{5}
Multiply -20 and -2 to get 40.
x=8
Divide 40 by 5 to get 8.
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}