The length of river a is 560 miles more than twice the length of river B. River A is also 1550 miles longer than river B. Find the lengths of river A and B.
a = 2b + 560 a = b + 1550 ---------------------- a - 2b = 560 a - b = 1550 --------------------- a - 2b = 560 -2(a - b = 1550) ------------------------ a - 2b = 560 -2a +2b = -3100 -a = -2540 a = 2540 ----------------------- 2540 = b + 1550 2540 - 1550 = b 990 = b