3 years ago

Solve to find the values of a and b.4a + 7b = 389a + 7b = 68

Mathematics

1 answer:

Nataliya [291]3 years ago

5 0

4a + 7b = 38 -> (1)
9a + 7b = 68 -> (2)

Subtract (1) from (2),
9a - 4a + 7b - 7b = 68 - 38
5a = 30
a = 6

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Solve to find the values of a and b.4a + 7b = 389a + 7b = 68​

Solve to find the values of a and b.4a + 7b = 389a + 7b = 68