Question

Consider the following pair of equations:

y = x + 4
y = –2x – 2

Explain how you will solve the pair of equations by substitution. Show all the steps and write the solution in (x, y) form.

Answer 1

{ y = x + 4
y = - 2 x - 2

Subsititute y = - 2 x - 2 :

[ (- 2 x - 2 ) = x + 4 ]

( - 2 x - 2 ) = x + 4

Add 2 to both sides:

- 2 x - 2 + 2 = x + 4 + 2

- 2 x = x + 6

Subtract x for