Question

x=2y+7
x=y+4
with substitution

Answer 1

x = 2y + 7      (*)

x = y + 4       (**)

Substitute (*) to (**):

2y + 7 = y + 4      subtract 7 from both sides

2y = y - 3        subtract y from both sides

y = -3

Put the value of y to the second equation:

x = -3 + 4

x = 1

Answer: x = 1 and y = -3 → (1, 3)