To sove a economic question i need to use algebra first.

P= - 1/4Qd+6.75

P = 1/2Qs + 2

So i got for the first step:

1/4 Qd = - p + 48

1/2 Qs = p - 2

but i need to get the 1/4 and 1/2 on the right side which i don't know how.

I would reall appreciate your help.