The equation would be h = 25 + m
^^^The reason this is the equation is because the amount of time it takes to do the homework is the 25 min of reading AND the m of completing math problems
Insert 20 in for m and solve for h
h = 20 + 25
h = 45
Insert 25 in for m and solve for h
h = 25 + 25
h = 50
Hope this helped!
~Just a girl in love with Shawn Mendes