Answer:
800 minutes
Explanation:
Make 2 expressions, one for Plan A, and one for Plan B
Plan A:
$9, and 0.17 per minute
9+0.17x
Plan B:
$25, and 0.15 per minute
25+0.15x
We want to find when they are the same, so we can set them equal to each other
9+0.17x=25+0.15x
Solve by isolating the variable, x
Subtract 9 from both sides
0.17x=16+0.15x
Subtract 0.15x from both sides
0.02x=16
Divide both sides by 0.02
x=800
At 800 minutes they will cost the same