is my this correct ..2 to the power of x =256.my answer was x=8 i want the rite answer?

Question

another question is 9 to the power of x+1=3 to the power of x-1

my answer was x =2 and 7..pls provide me the rite answer

Answer 1

2^x = 256
2^x = 2^8
so x = 8 that's correct.

The answer you found to your second question is wrong.
9^(x + 1) = 3^(x - 1)
(3^2)^(x + 1) = 3^(x - 1)
3^[2(x + 1)] = 3^(x - 1)

so...
2(x + 1) = x - 1
2x + 2 = x - 1
x + 2 = -1
x = -3

Answer 2

Yes, 2^8 = 256, so you are correct.
For the second one, use 9 = 3².
So 3^(2x+2) = 3^(x-1).
2x+2 = x-1
x = -3.
Let's check:
9 ^ -2 = 1/81
3^ -4 = 1/81.