Question 466700
Substitute x = 2y+1 in the equation 3x-y = 13

3(2y+1) - y  = 13
6y+3 - y = 13
5y = 10
y = 2

substitute y = 2 in 
x = 2y+1
x = 2(2) + 1
x = 5

Answer: y = 2
        x = 5