Questions on Algebra: Logarithm answered by real tutors!

Tutors Answer Your Questions about logarithm (FREE)

Question 303538: The loudness L of a sound measured in decibles (db) is given by the formula: L=10*log (I ÷ I0) where I repesents the intensity of the sound measured in watts per square meters and Io = 10^-12.
The loudness of certain sound measures 30 db. If the intensity of the sound is multiplied by 10, what is the loudness in decibels of the new sound?

Click here to see answer by stanbon(57966)

Question 303548: solve. 5-ln x=7
Click here to see answer by nerdybill(7003)

Question 303567: log(7)x=5 the answer I got is x=16,954 and also log x =1 the answer I got is x=10 log(4) (x-3) = log(4) (x-3)=1 the answer I got is x=3 just not sure if I am right on these problems...I am having hard time understanding this.....and one I have no clue how to do is e^t=1000 any help would be greatly appreciated....thanks in advance
Click here to see answer by Theo(3504)

Question 303588: Solve this equation:
(log base6 x)^2 - 3*(log base 6 x) - 2 = 0
Click here to see answer by stanbon(57966)

Question 303926: How do I solve this without a calculator?
1/27=3^2x
Click here to see answer by JBarnum(2044)

Question 303926: How do I solve this without a calculator?
1/27=3^2x
Click here to see answer by richwmiller(9144)

Question 303926: How do I solve this without a calculator?
1/27=3^2x
Click here to see answer by Alan3354(31518)

Question 303963: PLease help!!!!!!!!!!!!!
logπ 80
Click here to see answer by Alan3354(31518)

Question 303956: log2 (x + 4) = 3 + log2 (x - 5)
Please help!!!!!! Thank you so much!!!!!!! You guys are the best!!!!!!!
Click here to see answer by nerdybill(7003)

Question 303957: Please Help!!!!!!!!!!!!

2(x + 1) = 4

Click here to see answer by Alan3354(31518)

Question 303957: Please Help!!!!!!!!!!!!

2(x + 1) = 4

Click here to see answer by math1970(1)

Question 304010: How do I solve this?
0.1^n=100
Click here to see answer by richwmiller(9144)

Question 303952: Radium has a half-life of 1620 years. Write the decay function for a 3-mg sample. Find the amount of radium remaining after 50 years.
Click here to see answer by ankor@dixie-net.com(15746)

Question 304023: how do I solve log sqrt of 5 260.1 ?
Click here to see answer by stanbon(57966)

Question 303982: Solve: ln (x-5) + ln ( x+4)=ln 36
Click here to see answer by stanbon(57966)

Question 304049: If log base 10 of 1000 is 3 then what would the official name of the 1000 be in an logarithm equation?
Click here to see answer by unlockmath(1614)

Question 304070: The number B of bacteria in a Petri dish culture after t hours is given by B(t)=35e^0.368t When will the number of bacteria be 550?
Click here to see answer by nerdybill(7003)

Question 304136: I've no knowledge whatever of logarithms. If Log10x=3, then x=? Answer and steps would help me prep for accuplacer. Thanks much, smart people! Mike
Click here to see answer by dabanfield(803)

Question 304284: Please help with this question:
log(x-1)(x^2+x+1) - log(x^2+x+1)= 2
Click here to see answer by nerdybill(7003)

Question 304247: which equation is equivalent to 3log4+log6-log8 ?
a. log48
b. log1738
c. 3log2
d. 3log3
Click here to see answer by nerdybill(7003)

Question 304490: how do u evaluate log (base 16) 64
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Question 304516: 2logx+log11
Click here to see answer by stanbon(57966)

Question 304611: what is the value of x in the logarithm log(base)3(x^2-4)-Log(base)3(x+2)=2
Click here to see answer by nerdybill(7003)

Question 304675: log(5x+8)=1+log(x-5)
solve for x
I keep getting 58/5, which is obviously incorrect
Click here to see answer by stanbon(57966)

Question 304708: please simplify 2log5+2log2
Click here to see answer by nerdybill(7003)

Question 304784: For a>0 and b>0, log a/b =
Click here to see answer by richwmiller(9144)

Question 304777: Pleaseee!!! And Thank you! " Expand the log: Log -no base- 7(3x-2)^2 "
Click here to see answer by london maths tutor(243)

Question 304777: Pleaseee!!! And Thank you! " Expand the log: Log -no base- 7(3x-2)^2 "
Click here to see answer by Alan3354(31518)

Question 304781: Express as a power of x.

Click here to see answer by Edwin McCravy(8999)

Question 304839: Please help me express as a power of X
Click here to see answer by themathtutor2009(81)

Question 304867: 5+ln(8x)=23-2ln(x)
Click here to see answer by nerdybill(7003)

Question 304867: 5+ln(8x)=23-2ln(x)
Click here to see answer by themathtutor2009(81)

Question 304877: 2log(x)-2 = log(x-25)
Click here to see answer by Alan3354(31518)

Question 304889: log2^x = log2^5 +3
Click here to see answer by themathtutor2009(81)

Question 304913: Find the exact value of x for which:
4^x * 5^(4x+3) = 10^(2x+3)
I am aware that this question involves the change base rule, but i really need some guidance on where to start. Your help would be much appreciated!
Click here to see answer by scott8148(6628)

Question 305063: 2log(x+2)=log3+log(2x+1)
Click here to see answer by nerdybill(7003)

Question 305159: log(base)3(x-4)-log(base)3(x-10)=1
Click here to see answer by nerdybill(7003)

Question 305274: what is the value of x in the equation (3^x)=148, expressed to the nearest hundreth?
Click here to see answer by josmiceli(9817)

Question 305275: solve for x: 2^(4x-1)=4^x
Click here to see answer by scott8148(6628)

Question 305432: I need help with this problem 7+3Log(x)= 19
would I move the seven over? Thank you
Click here to see answer by nerdybill(7003)

Question 305437: 0.07t
2e =6
The 0.07t is above the e.

Do I divide the 2 on each side?
Click here to see answer by Edwin McCravy(8999)

Question 305433: -3x
14 =1

The -3x is above the 14
Click here to see answer by edjones(7569)

Question 305467: Hello, I have a question about how to write a expression as a single logarithm
the expression is:
125^9x-2=150
Thank you.
Click here to see answer by Fombitz(13828)

Question 305490: ln(x+3)/ln(x-3)=2
Click here to see answer by stanbon(57966)

Question 305435: IN(4p)=0
would I divide the 4 by something?
Click here to see answer by Fombitz(13828)

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