Question

A pair of equations is shown below.

x + y = 2
y = one halfx + 5

If the two equations are graphed, at what point do the lines representing the two equations intersect?

(4,-2)
(-2,4)
(2,5)
(5,-2)

Answer 1

Your answer is B) (-2,4).

Explanation:

Answer 2

I'll solve it by substitution instead of graphing.

x + y = 2
y = (1/2)x + 5

Substitute equation 2 into equation 1.

x + (1/2)x + 5= 2

(3/2)x + 5 = 2

(3/2)x + 5 - 5 = 2 - 5

(3/2)x = -3

(2/3) * (3/2)x = -3 * (2/3)

x = -2

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

x = -2
y = 4

(-2,4)

Your answer is B) (-2,4).