8^x=8^0
The 8 in both sides gets cancelled out.
x=0
100^x=100
The hundred in both sides gets cancelled out.
x=1
12^x times 12^4=12^8
When the bases (numbers) are same and are multiplied together, you add the powers together.
12^x+4=12^8
The 12 in both sides get cancelled out.
x+4=8
x=8-4
x=4
(7^2)^9=7^3)^x
When there are powers both inside and outside the brackets, they’re multiplied with each other.
7^18=7^3x
The seven in both sides gets cancelled out.
18=3x
3x=18
x=18/3
x=6