Answer:
x = 1 and y = 4
Step-by-step explanation:
Because y = x + 3 we can substitute 3y with 3(x + 3)
4x + 3(x + 3) = 16
4x + 3x + 9 = 16
7x + 9 = 16
7x + 9 - 9 = 16 - 9
7x = 16 - 9
7x = 7
7x ÷ 7 = 7 ÷ 7
x = 7 ÷ 7
x = 1
Since y = x + 3 and x = 1 y = 4.
1 + 3 = 4
x = 1 and y = 4
Check:
x = 1 and y = 4
1 x 4 + 3 x 4 = 16
4 + 12 = 16
