math
posted by shanquessa .
Hi, I am taking Algebra 2 and I need help with some Substitution method problems:
x+12y=68
x=8y12
x+3y=7
2x4y=24
3a+b=3
2a5b=15
6=3x6y
4x=4+5y

I'll do one for you. They all work the same way. You need the practice doing them yourself.
Substitute 8y  12 for x in the first equation.
8y  12 + 12y = 68
20 y = 80
y = 4
x = 8y  12 = 32  12 = 20