Question

4a + 6b = 10
2a - 4b =12
What does 12a equal?

Answer 1

multiply second equation by 2 and rewrite

4a + 6b = 10

4a - 8b = 24

subtract equations

0 + 14b = -14

14b = -14

b = -1

sub back into 4a + 6b = 10 to find the value of a

4a + 6 (-1) = 10

4a - 6 = 10

4a = 16

a = 4

therefore, 12a = 12×4

12a is 48