Answer:
Michaela's dinner was $30
Explanation:
In order to find this, we write the following equation.
(40 + x)*.15 = 10.50
In this equation, x represents the cost of Michaela's dinner. The 40 would be Mike's dinner and we need to multiply that by the tip rate to find the tip of 10.50. Now we can solve for x.
(40 + x)*.15 = 10.50
40 + x = 70
x = 30