SOLUTION: Solving log(x^2-15)=1 Do not know how to solve for this. The answer is +or- 5, but don't know how to get that answer.

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Question 923675: Solving log(x^2-15)=1
Do not know how to solve for this. The answer is +or- 5, but don't know how to get that answer.
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
log(x^2-15)=1
log(x^2-15)= log(10)
x^2-15 = 10
x^2 = 25
etc

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

log%28x%5E2-15%29=1 ...you have log base 10, then we can write 1 as log%2810%29 because log%2810%2C10%29=1

log%28x%5E2-15%29=log%2810%29 ...if log same, then x%5E2-15=10 is same too
x%5E2-15=10...solve for x
x%5E2=10%2B15
x%5E2=25
x=sqrt%2825%29
so, x=5 or x=-5