Answer:For example, choice A is incorrect because if the value of 10x + 3 were 4, then it would follow that x = 0.1, and the value of 5x + 6 would be 6.5, not 10.
Step-by-step explanation:
The answer is
3a + 5 = 12
subtract 5 from both sides
3a = 7
divide by 3 on both sides to isolate "a"
a = 7/3
Substitute 7/3 for "a" in the second equation
6(7/3) + 14
6 multiplied by 7/3 = 42/3 = 14
14 + 14 = 28
