Zachery purchased a computer for $1,200 on a payment plan. What is an equation that models the balance y after x months?

Question

Zachery purchased a computer for $1,200 on a payment plan. Three months after he purchased the computer, his balance was $855. Four months after he purchased the computer, his balance was $740. What is an equation that models the balance y after x months?

Answer 1

 

 MOnth    Balance

  0            1200

 3              855

 4              740

 

 

Slopes:

(1200 - 855)/3 = 345/3 = 115

(1200 - 740)/4 = 460/4 = 115

(855-740)/1 = 115

 

y = 1200 - 115*x