Question

If 2x+3 – 2^x = k(2^x), what is the value of k?A) 3B) 5C) 7D) 8

Answer 1

Solution

For this case we can do the following:

$2^{x+3}-2^x=k(2^x)$

We can do the following

$2^x(2^3-1)=k(2^x)$

By direct comparison we have:

$2^3-1=8-1=7=k$

then the answer is:

c) 7