Solve for x
x=4y+9
Solve for y
y=\frac{x-9}{4}
Graph
Share
Copied to clipboard
2x=18+8y
Add 8y to both sides.
2x=8y+18
The equation is in standard form.
\frac{2x}{2}=\frac{8y+18}{2}
Divide both sides by 2.
x=\frac{8y+18}{2}
Dividing by 2 undoes the multiplication by 2.
x=4y+9
Divide 18+8y by 2.
-8y=18-2x
Subtract 2x from both sides.
\frac{-8y}{-8}=\frac{18-2x}{-8}
Divide both sides by -8.
y=\frac{18-2x}{-8}
Dividing by -8 undoes the multiplication by -8.
y=\frac{x-9}{4}
Divide 18-2x by -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}