In this problem, we know that
the initial balance is $800
then
$717.50, $635,$552.50
I will verify if the relation is linear
Let
y ----> the balance in dollars
x ----> number of months
y=mx+b
Find out the slope
we need two points
so
(0,800) and (1, 717.50)
m=(717.50-800)/(1-0)
m=-82.5
therefore
The linear equation is
y=-82.5x+800
Verify
For x=3
y=-82.5(3)+800=552.5 ----> is correct
therefore
The answer is
y=-82.5x+800
