SOLUTION: solve the equation e^(2x)=20 for x .... a. x=10/e b. x=1n20/2 c. x=1n10 d. x=20-e/2 tthanks!

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: solve the equation e^(2x)=20 for x .... a. x=10/e b. x=1n20/2 c. x=1n10 d. x=20-e/2 tthanks!      Log On


   

Question 308007: solve the equation e^(2x)=20 for x ....
a. x=10/e
b. x=1n20/2
c. x=1n10
d. x=20-e/2
tthanks!
Found 2 solutions by Fombitz, rapaljer:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
e%5E%282x%29=20+
ln%28e%5E%282x%29%29=ln%2820%29
2x=ln%2820%29
x=%281%2F2%29ln%2820%29
I'm not sure which answer it is but this is the correct answer.

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Start by taking the ln of each side of the equation to "undo" the "e^":
e%5E%282x%29=20
ln%28e%5E%282x%29%29=+ln+20
2x=+ln+20

Divide by 2:
x=+ln20%2F2

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Seminole State College of Florida
Altamonte Springs Campus