Algebra 1 question

Question

In some cases the answers you will get won’t make physical sense or need a bit of interpreting. Look at the next example and be careful when you interpret your final solution.

Tanisha’s plan: $0.15 per minute used talking and a $25 monthly fee.

Rebecca’s plan: $0.10 per minute used talking and a $18.50 monthly fee.

Figure out after how many minutes the two plans will charge the same amount?

Answer 1

25.00 + 0.15m = 18.50 + 0.10m

Can you solve for m and answer?

Answer 2

Let x be the minutes used

Tanisha cost : 25 + 0.15 x

Rebecca cost : 18.50 + 0.10 x

Same when

25 + 0.15x = 18.50 + 0.10 x

0.05x = -6.5

x = -130

Obviously x<0 is impossible, so the answer is never