Judging by the question you have provided I have figured that the best way to go about finding the solution is by using the distributive property!
This means you will want to distribute the y = -3 into the 2y+7-4y-10 equation.
However, the first step you should take is to simplify the equations. After simplifying the equations you should come out with the new equation being -2y-3.
You now want to distribute the y=-3 into the equation! You should get -2(-3)-3. Now solve!
