Hi,
Equation;
[tex] - 17 =  \frac{2y}{3}  +  \frac{3y}{4}  [/tex]
Solving:
[tex] - 17 =  \frac{2y}{3}  +  \frac{3y}{4}    \:  \:  \:  |  \div 12 \\  - 204 = 8y + 9y \\  - 204 = 17y \\ 17y =  - 204  \:  \:  \:  |  \div 17 \\  \\ y =  - 12 \:  \:  \:  \:  \:  \:  \:  \: (result)[/tex]
Hope this helps.
r3t40