ab=44 --------- (1)
bc=112 --------- (2)
a+c=13 --------- (3)
from (3), a = 13 - c.
from (2), b = 112/c.
Substitute for a and b into (1), giving
(13 - c)*(112/c) = 44 multiply both sides by c.
112(13 - c) = 44c
1456 - 112c = 44c
156c = 1456
c = 9 1/3 = 28/3
b = 112/c = 112*3/28 = 12
a = 13 - c = 3 2/3 = 11/3
Answers: a = 11/3, b = 12, c = 28/3