Problem Solving (PS) | If x and y are integers and 7x−7x−2=3∗14y, what is the value of x?

This was a very challenging problem and really tests all your power laws. It's tempting to guess X =2 because if Y =1 the math works.

However we should solve to ensure. 14^Y is the same as (2*7)^Y which is the same as 2^Y X 7^Y. Anyways the solution follows. Also 7^(x+2) is the same as 7^X * 7^2. On top of all this they make it a 7^X * 7-2.

Attachments
gmat 30.png [ 503.67 KiB | Viewed 10 times ]

---