Answer:a=-7
Step-by-step explanation:The given equation is 3(a-7)=6a
Using distributive rule we have:
3a-21=6a
21 is subtracted to 3a .We always perform the opposite operation both sides.
Opposite of subtraction is addition
Adding 21 both sides
3a=6a+21
Subtracting 6a both sides:
3a-6a=21
-3a=21
Dividing both sides by -3 we have
a=-7.
