Solve for x
x=7
Graph
Share
Copied to clipboard
-7x+56=4x-21
Use the distributive property to multiply -7 by x-8.
-7x+56-4x=-21
Subtract 4x from both sides.
-11x+56=-21
Combine -7x and -4x to get -11x.
-11x=-21-56
Subtract 56 from both sides.
-11x=-77
Subtract 56 from -21 to get -77.
x=\frac{-77}{-11}
Divide both sides by -11.
x=7
Divide -77 by -11 to get 7.
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}