A medical insurance company offers two prescription-drug insurance plans. With plan 1, James would pay the first $150 of his prescription costs and 50% of all costs after that. With plan 2, James would pay the first $280 of costs, but only 20% of the rest. For what amount of prescription costs will plan 2 save James money? (Assume that his prescription costs exceed $280.) mostly need help on how to do the problem

when expenses are greater than $433.33

Step-by-step explanation:

set up equations for each plan

let 'x' = prescription costs

Plan 1:  y = 150 + .5x

Plan 2:  y = 280 + .2x

150 + .5x = 280 + .2x

.5x = 130 + .2x

.3x = 130

x = 433.33

i checked my answer by graphing each equation and $433.33 is the break-even point where each plan would have the same costs but, after that, the expenses for Plan B are less

i leave the calculator work to you.

7. diameter 4 miles, circumference 4π miles

8. radius 0.2 miles, circumference 0.4π miles

[this is a bad problem because the actual radius of a car on the track is less than 0.2 miles so the answer is less than 0.4π miles]

9. radius 6 feet, circumference 12π feet

10. diameter 14 cm, circumference 14π cm

11. diameter 4.8 feet, circumference 4.8π feet