Question #3efa2
1 Answer
Jan 18, 2017
Explanation:
Repeated addition is multiplication. Thus:
overbrace(2^x+2^x+2^x+2^x)^("repeated 4 times")=2^72
4(2^x)=2^72
Let's write this all with the same base:
2^2(2^x)=2^72
Using the rule
2^(2+x)=2^72
Equating the powers:
2+x=72
x=70