Answer:
y=0.2x+29
Step-by-step explanation:
Given that:
y is the total monthly of the A Fee and Fee plan.
x is the number of monthly minutes used.
- If a customer uses 290 minutes, the monthly cost will be $87, we have the pair (290, 87)
- If the customer uses 980 minutes, the monthly cost will be $225, this is the coordinate pair (980, 225).
We want to obtain an equation in the form: y=mx+b
First, let us determine the slope, m
Given points (290, 87) and (980, 225):
<u>Slope</u>

Next, we determine the y-intercept, b.
Substituting the pair (290, 87) and m=0.2 in y=mx+b, we obtain
87=0.2(290)+b
b=87-0.2(290)=29
Therefore, our equation in the form y=mx+b is:
y=0.2x+29