Answer: Answer is (-3, 7)
Explanation:
y = -x + 4 equ 1
y = 3x + 16 equ 2
Make x subject of formular in equ 1
x = 4 - y equ 3
Subatitute x = 4 - y in equ 2
y = 3(4-y) +16
y = 12 - 3y + 16
y + 3y = 12 + 16
4y = 28
y = 28/4 = 7
Substitute y = 7 in equ 1
7 = -x + 4
7 - 4 = -x
x = -3
Answer is (-3, 7)