Solve for x
x=\frac{y+84}{21}
Solve for y
y=21\left(x-4\right)
Graph
Share
Copied to clipboard
42x=168+2y
Add 2y to both sides.
42x=2y+168
The equation is in standard form.
\frac{42x}{42}=\frac{2y+168}{42}
Divide both sides by 42.
x=\frac{2y+168}{42}
Dividing by 42 undoes the multiplication by 42.
x=\frac{y}{21}+4
Divide 168+2y by 42.
-2y=168-42x
Subtract 42x from both sides.
\frac{-2y}{-2}=\frac{168-42x}{-2}
Divide both sides by -2.
y=\frac{168-42x}{-2}
Dividing by -2 undoes the multiplication by -2.
y=21x-84
Divide 168-42x by -2.
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}