Question

What is the solution to the equation 2^x+4 -12=20? A. x=0 B. x=1 C. x=2 D. x=9

Answer 1

2^x+4 -12=20
2^x+4 = 20+12
2^x+4 = 32
2^x+4 = 2^5
x+4 = 5
x = 1

answer is B. x=1

Answer 2

Given: The equation $2^{x+4} -12=20$

To Find: The value of x

Solution: $x=1$

Calculation/Explanation:

We simplify the given equation in the usual way, as follows:

$2^{x+4}-12=20\\2^{x+4}=20+12\\2^{x+4}=32\\2^{x+4}=2^{5}$

Now, we use the property that if two sides of the equation are equal and have the same base, then the exponents too must be equal.

So we have

$2^{x+4} =2^{5}\\x+4=5\\x=1$

Therefore option B is correct, i.e., $x=1$