Question

Zachary purchased a computer for $1,800 on a payment plan. Three months after he purchased the computer, his balance was $1,365. Four months after he purchased the computer, his balance was $1,220. What is an equation that models the balance y after x months?

Answer 1

Y=1800-(time)(payment)
1365=1800-3(x)
1220=1800-4(x)