Answer:
q = 3.5
Step-by-step explanation:
-15 = 5(3q - 10) - 5q
-15 = (5*3q + 5*-10) - 5q
-15 = 15q - 50 - 5q
-15 + 50 = 15q - 5q
35 = 10q
q = 35/10
q = 3.5
Check:
-15 = 5(3*3.5 - 10) - 5*3.5
-15 = 5(10.5 - 10) - 17.5
-15 = 5*0.5 - 17.5
-15 = 2.5 - 17.5
