Question

4a + 6b= 10 2a - 4b =12 what does 12a=

Answer 1

4a + 6b = 10
2a - 4b = 12...multiply by -2
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4a + 6b = 10
-4a + 8b = - 24 (result of multiplying by -2)
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14b = - 14
b = -14/14
b = -1

2a - 4b = 12
2a - 4(-1) = 12
2a + 4 = 12
2a = 12 - 4
2a = 8
a = 8/2
a = 4

so 12a = 12(4) = 48 <==