To solve the equation 2^x-3 + 2^x+1 = 136, we can simplify it by combining the terms with the same base, which is 2.

2^x-3 + 2^x+1 = 136

Rewriting the exponents:

2^(x-3) + 2^(x+1) = 136

Now, let's rewrite 136 as a power of 2:

136 = 2^7

Substituting this into the equation:

2^(x-3) + 2^(x+1) = 2^7

Since the bases are the same, we can set the exponents equal to each other:

x - 3 + x + 1 = 7

Combining like terms:

2x - 2 = 7

Adding 2 to both sides:

2x = 9

Dividing both sides by 2:

x = 4.5

Therefore, the solution to the equation 2^x-3 + 2^x+1 = 136 is x = 4.5.