Answer:
see below
Step-by-step explanation:
bh + hr = 25
Factor out an h
h( b+r) = 25
Divide each side by ( b+r)
h( b+r)/( b+r) = 25/( b+r)
h = 25/( b+r)
Now solve for r
bh + hr = 25
Subtract bh from each side
bh -bh+ hr = 25-bh
hr = 25 -bh
Divide by h
hr/h = 25/h -bh/h
r = 25/h -b
