Answer:
y = 2,500x + 5,000
Rate of change = $2500 a year
Initial value = $5000
Step-by-step explanation:
We have 3 values to figure what is the function here, the rate of change, and the initial value.
To find the initial value, find where y is located where x is 0. In this case it's $5000, so that's the initial value.
Now the rate of change. Find y where x is 1. That is $7,500. Subtract $5000 from to get the rate of change, since it's the same. It's constant because of a straight diagonal line.
$7,500 - $5,000 = +$2,500/year
Now the equation. This is not proportional, because y's starting point is not 0. It's greater than that, so an addition sign is in the equation. Do you remember our initial value? That's right! It was $5,000, so put that after the addition sign.
y = ????x + 5,000
You also need to remember the rate of change, which was 2,500. Put that on the left of the addition sign and there's your equation!
y = 2,500x + 5,000
