Question

Zachary purchased a computer for $1,500 on a payment plan. Six months after he purchased the computer, his balance was $600. Eight months after he purchased

the computer, his balance was $300. What is an equation that models the balance y after x months?
The equation models the balance y after x months

Answer 1

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Answer:

y = 1500 -150x

Explanation:

Apparently, we're to assume that the balance is linear function of the number of months. We are given 3 points:

(0, 1500), (6, 600), (8, 300)

Any two of these can be used to write the equation of the line using the 2-point form:

y = (y2 -y1)/(x2 -x1)(x -x1) +y1

y = (600 -1500)/(6 -0)(x -0) +1500

y = -900/6x +1500

y = 1500 -150x . . . models the balance after x months