Solve for r
r=\frac{x+30}{2}
Solve for x
x=2\left(r-15\right)
Share
Copied to clipboard
2r+5=35+x
Add x to both sides.
2r=35+x-5
Subtract 5 from both sides.
2r=30+x
Subtract 5 from 35 to get 30.
2r=x+30
The equation is in standard form.
\frac{2r}{2}=\frac{x+30}{2}
Divide both sides by 2.
r=\frac{x+30}{2}
Dividing by 2 undoes the multiplication by 2.
r=\frac{x}{2}+15
Divide 30+x by 2.
-x+5=35-2r
Subtract 2r from both sides.
-x=35-2r-5
Subtract 5 from both sides.
-x=30-2r
Subtract 5 from 35 to get 30.
\frac{-x}{-1}=\frac{30-2r}{-1}
Divide both sides by -1.
x=\frac{30-2r}{-1}
Dividing by -1 undoes the multiplication by -1.
x=2r-30
Divide 30-2r by -1.
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}