Solve, by method of substitution, the simultaneous equations: 5x+y=22 2x+y=10

Solve by substitution:5x + y = 22 (1)2x + y = 10 (2)
First let us label the equations 1 and 2. In order to solve this set of equations we need to rearrange one of the equations so that we have one of the variables (x or y) equal to some expression, or in other words we need to make one of the variable the subject.
I am going to make y the subject in equation (1).
5x + y = 22 -5 -5 (we subtract 5 from both sides)
y= 22 -5x I'll call this equation (3).
So now I substitute (3) into (2) to get:
2x + (22 -5x) = 10
Rearrange to make x the subject:
22 -3x =103x = 12x = 4
Now we sub x=4 into equation (1).
5(4) + y = 2220 + y = 22y = 2
Answer x=4 y=2