Answer:
8.8 hours
Explanation:
happy paws charges $21 in addition to $2.5 per hour -- we can write this as
21 + 2.5 per hour -- since the number of hours is x, this is equal to
21 + 2.5 (x)
similarly, woof watchers is
10 + 3.75 (x)
we must find when the services are equal --
21 + 2.5x = 10+3.75x
subtract 10 from both sides
11 + 2.5x = 3.75x
subtract 2.5x from both sides
11 = 1.25
divide both sides by 1.25
x = 8.8