Solve 2 log x = log 36

Question

Solve 2 log x = log 36
Choose one answer.
A. x = ±6
B. x = 6
C. x = 18
D. x = 72

Answer 1

2logx = log(x²)

 

So, log(x²) = log36

 

Therefore, x² = 36

 

x = ±6

 

If x = -6, then 2logx is undefined.  

 

So, x = 6 

Answer 2

2log x = log 36

 

Divide both sides of equation by 2.

 

log x = 0.778

 

 

Rewrite the log equation in exponential form.

 

10^0.778 = x

 

5.998 = x

 

 

The solution is (B).