Can someone please help me with this I am so confused I have been working on it for 2 hrs!!

Question

Bayside Insurance offers two health plans under plan A Gary would have to pay the first $70 off his medical bills plus 30% of the rest. Under plan B Gary would pay the first $170 but only 20% of the rest. For what amount of medical bills will plan B save Gary money. Assume that Gary has over $170 in bills

Gary would save with plan b if she has over $? In bills

Answer 1

Let the amount of bills be X. The amount paid in plan A is then
70 + 0.3(X-70)
With plan B, the amount paid is
170 + 0.2(X-170)

The two amounts are equal when
70 + 0.3(X-70) = 170 + 0.2(X -170)
0.3X - 21 = 100 + 0.2X -34
0.1X = 87
X = $ 870
With bills of $870, he pays $310 with either plan.
If bills are higher than that, plan B is better.

Answer 2

Thank you so much for explaining this