Explanation:
substitution means that we use one equation to express one variable by the other. with that e go into the other equation to solve for the now single variable.
with that we then go back into one of the original equations to solve for the second variable.
x + 3y = 22
2x - y = 2
from the first equation we get
x = 22 - 3y
and that we use more in the second equation
2(22 - 3y) - y = 2
44 - 6y - y = 2
42 - 7y = 0
42 = 7y
y = 6
now we use that e.g. in the second original equation
2x - 6 = 2
2x = 8
x = 4
so, (4, 6) is the solution.