Question

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.

Answer 1

a = 2b + 560
a = b + 1550
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a - 2b = 560
a - b = 1550
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a - 2b = 560
-2(a - b = 1550)
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a - 2b = 560
-2a +2b = -3100
-a = -2540
a = 2540
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2540 = b + 1550
2540 - 1550 = b
990 = b

Answer 2

River B is 990 miles and River A is 2,540 miles.