Question

How can I solve 16,18,20, and 22?

Answer 1

Problem 16 Begin by setting corresponding positions equal to each other.
9 = x + 2y  and 13 = 4x + 1
The second equation only has one variable so you should solve it first.
13 = 4x + 1
13 - 1 = 4x + 1 - 1
12 = 4x  (divide both sides by 4)
3 = x
you can use this value to find y in the other equation
9 = 3 + 2y
9 - 3 = 3 - 3 + 2y
6 = 2y
3 = y