Solve this Equasion

Question

x=2y
4x+y=12
using the substitution method.
Please give solution

Answer 1

Use 2 y for x in the second equation
4 *(2 y) + y = 12
8 y + y = 12
9 y = 12
y = 12/9
y = 4/3
then go back and get x from x = 2 y
x = 2 y
x = 8/3

then check
x = 2*4/3 = 8/3 yes
4(8/3) + 4/3 = 12 ?
32/3 + 4/3 = 12?
36/2 = 12?
12 = 12 ? yes, check