Question

Solve the system.
y = 4x + 12 and y = -2x + 6

Answer 1

x=-1, y=8

Answer 2

Solving by substitution:

(1) y = 4x + 12
(2) y = -2x + 6
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in y = -2x + 6, substitute (4x + 12) for y in equation 2. This comes from the first equation.

4x + 12 = -2x +6
6x = -6
x=-1

From (1) y = 4x + 12, substitute -1 for x.

y = 4 (-1) +12 = 8

Solution (-1,8)