Respuesta :

Answer:

a = 3 and b = 4

Step-by-step explanation:

5a + 4b = 31 --(1)

5a + 6b = 39 --(2)

(2) - (1) : 2b = 8

               b = 4 -- (3)

Substituting (3) into (1),

5a + 16 = 31

5a = 15

a = 3 -- (4)

Therefore, a = 3 and b = 4

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