Solve for y
y=7
Graph
Share
Copied to clipboard
3.5y+31.5=8y
Use the distributive property to multiply 3.5 by y+9.
3.5y+31.5-8y=0
Subtract 8y from both sides.
-4.5y+31.5=0
Combine 3.5y and -8y to get -4.5y.
-4.5y=-31.5
Subtract 31.5 from both sides. Anything subtracted from zero gives its negation.
y=\frac{-31.5}{-4.5}
Divide both sides by -4.5.
y=\frac{-315}{-45}
Expand \frac{-31.5}{-4.5} by multiplying both numerator and the denominator by 10.
y=7
Divide -315 by -45 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}