The way it is written, none of them.

The "a"s cancel out.
Answer:
a
Step-by-step explanation:
Answer: ? Wha?
Step-by-step explanation:
X=number of years that Ethas was 5 times older than his son.
we suggest this equation:
40-x=5(12-x)
40-x=60-5x
-x+5x=60-40
4x=20
x=20/4=5
answer. 5 years.