Respuesta :

Answer:

m = 35

Step-by-step explanation:

2m + m -15 = 90

3m -15 = 90

     +15  +15

3m = 105

/3     /3

m = 35

To check the work just insert 35 for m:

2(35) + 35 -15 = 90

70 + 35 -15 = 90

105 - 15 = 90

90 = 90