Question

7.(08.03)

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. (20 points!)

Answer 1

(-2, 2).

Explanation:

d

Answer 2

(-2, 2).

Explanation:

y = x + 4

y = - 2x - 2

Substitute y = x + 4 in the second equation:

x + 4 = -2x - 2

x + 2x = -2 - 4

3x = -6

x = -2.

Now substitute x = -2 in the first equation:

y = -2 + 4 = 2.

Check the results by substituting for x and y in equation 2:

2 = -2*-2 - 2 = 4 - 2 = 2. - this checks out.