Question

How do you solve `( y+2)/4 - (y-1)/5 =15`?

Answer 1

In this equation the only thing that bothers you should be de fractions, so you have to get rid of them.
You can do this just by multiply each side of the equation for the minimum common multiple, in this case is easy, just multiply for 45=20 each side, you can do this because you do it in both sides, if 5=5 then 520=5*20 right?

`20*((y+2)/4-(y-1)/5)=15*20`

as 20/4=5 and 20/5=4 the equations becomes a linnear equation, now it should be really easy for you to solve

`5*(y+2)-4*(y-1)=300`
`5y+10-4y+4=300`
`y+14=300`
`y=300-14=286`