The total length of 4 blue banner and 5 yellow banner is 49 m. The total length of 2 blue banner and 1 yellow banner is 17 m. All banner of the same colour have the same length. Find the length of a blue banner

Answer 1

4 b + 5 y = 49
2 b + 1 y = 17

4 b + 5 y = 49
10b + 5 y = 85
-----------------subtract
-6 b = -36
b = 6

Answer 2

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