Solve for r
r=5
Share
Copied to clipboard
-20r+32-2=-8r-30
Use the distributive property to multiply -4 by 5r-8.
-20r+30=-8r-30
Subtract 2 from 32 to get 30.
-20r+30+8r=-30
Add 8r to both sides.
-12r+30=-30
Combine -20r and 8r to get -12r.
-12r=-30-30
Subtract 30 from both sides.
-12r=-60
Subtract 30 from -30 to get -60.
r=\frac{-60}{-12}
Divide both sides by -12.
r=5
Divide -60 by -12 to get 5.
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}