Step-by-step explanation:
part a: Total is 10 hours
soccer: 2v + 1
volleyball: v
part b: 10 = 2v + 1
-2v = -10 +1
-2v = -9
v = -9 ÷ -2
v = 4.5
volleyball is 4.5 hours
if soccer is one hour longer than volleyball then soccer is 5.5 hours
4.5 + 5.5 is a total of 10 hours :)