SOLUTION: find the value of x 1.)logx (3x+10)=2

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Question 239794: find the value of x
1.)logx (3x+10)=2
Found 2 solutions by vleith, JimboP1977:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
logx+%283x%2B10%29=2
10%5E%28logx+%283x%2B10%29%29=+10%5E2
3x%2B10+=+100
3x+=+90
x+=+30
Check you answer. Does log(100) = 2 ??? yes it does

Answer by JimboP1977(311) About Me  (Show Source):
You can put this solution on YOUR website!
I got a different answer to vleith. In the question I assumed that log has a base of x? Is this incorrect?
log(base x) (3x+10) = 2 (This means what number power to base x gives 3x+10)
3x+10 = x^2
10 = x^2 - 3x
10= (x-(3/2))^2 - 9/4
(49/4)^(1/2) = x - (3/2)

x = +3.5 + 3/2 OR x = -3.5 + 3/2
x = 5 OR x = -2