Questions on Algebra: Logarithm answered by real tutors!

Tutors Answer Your Questions about logarithm (FREE)

Question 376201: log x = 4^x
Click here to see answer by Fombitz(13828)

Question 375866: how to solve:
log2x-log(x-7)=log3

Click here to see answer by ewatrrr(10682)

Question 376203: solve for x
3^(x-2)=7
Click here to see answer by Fombitz(13828)

Question 376205: change from logarithmic form to exponential form
log[x]=3
Click here to see answer by ewatrrr(10682)

Question 376205: change from logarithmic form to exponential form
log[x]=3
Click here to see answer by nerdybill(7012)

Question 376214: log(x)=3
Click here to see answer by nyc_function(2733)

Question 375902: Its a word problem and i am not sure how to solve it?
A forensic specialist took the temperature of a victim's body lying in a street at 2:10 a.m. and found it to be 85.7'F. At 2:40 a.m., the temperature of the body was 84.8'F. When was the murder committed if the air temperature during the night was 55'F? [Remember, normal body temperature is 98.6'F.]
HELP! Please and Thank You
Click here to see answer by ankor@dixie-net.com(15747)

Question 376224: log((n-2)^3{n-5}/n^2)
Click here to see answer by Fombitz(13828)

Question 376226: If 3^(2x) + 9 = 10(3^x) solve for x.
I know that x = 2 but only because of guess an check. I know I need to use a log somewhere and other basic algebra but I can't figure out what all the steps are. I have looked through my book and some sites online and they didn't help.
Thanks!
Click here to see answer by Fombitz(13828)

Question 376321: the problem is: 3^4x-5 = 9^7x
i forget whether or not the 3 and the 9 are the same base 10, or whether you need to use the change of base formula and I can't find an example like this is my notes.
Click here to see answer by jim_thompson5910(28717)

Question 376325: If 500 milligrams of anestesia are injected into a patient prior to surgery and the amout A in milligrams in the patient after t hours is given by the equation A=500e-0.165t the -0.165t is suppose to be up like a square on 500e but didn't know how to put it up there.
a) the amount of anestesia left after 5 hours.
b) when the amount of anesthesia remaining in the patient will be 100mg.
Can you help ! I'm suppose to do it on the calulator but can't figure it out.
Click here to see answer by jim_thompson5910(28717)

Question 376339: 3lnx-3lny-ln2+1/2lnz
Click here to see answer by user_dude2008(1861)

Question 376343: Condense the following single logarithmic. 5 log x -2 log y +8 log z-3 log w

Click here to see answer by user_dude2008(1861)

Question 376396: how to solve (4/3)^1-x =5^x
Click here to see answer by solver91311(17077)

Question 376401: I need help. I am stuck on this one. How do I graph the following:
y=(2^x+1)+3 and y=log(x)^2+1
Thank you very much
Click here to see answer by Fombitz(13828)

Question 376579: I have to solve for x and the problem says. e^(-15x)=1000 what I tried was to take the Ln in both sides and then solve but im not sure could you help me please?
Click here to see answer by ankor@dixie-net.com(15747)

Question 376611: logx -log7-log8
written as a single logarithm

Click here to see answer by jim_thompson5910(28717)

Question 376640: Any help would be greatly appreciated on this equation: log(x+84)-log(x+9)=log(x)
Click here to see answer by ankor@dixie-net.com(15747)

Question 376720: Determine the principal P that must be invested at rate r, compounded monthly, so that $500,000 with be available for retirement in t years:
r=12%, t=40
Click here to see answer by rfer(12731)

Question 376753: Write as a single log expression:
2log(x+1)-2log(x-1)
just log[(x+1)^2/(x-1)^2] ??
Click here to see answer by Fombitz(13828)

Question 376752: Write as a single log expression:
2(log(x)+log(x^2+1))-3log(x-2)
log(x^2)+log(x^4+1)-log(x^3-8)
log(x^2(x^4+1)-log(x^3-8)
log(x^6+x^2)-log(x^3-8)
log(x^12)-log(x^3-8)
log[(x^12)/(x^3-8)]
???
Click here to see answer by solver91311(17077)

Question 376796: solve. logx(that is base x) 9/16(that is a fraction)=2
Click here to see answer by Alan3354(31538)

Question 376797: Write Logb(that is base b)x^3y^2/z(that is a fraction) in terms of the logarithms of x, y, and z.
Click here to see answer by jsmallt9(3296)

Question 377107: what is the solution to this exponential inequallity;

2^(x^5-x^2)< 1
I need to express the answer in interval notation
Click here to see answer by Edwin McCravy(8999)

Question 377487: 3(9)^(x-1)=(81)^(2x+1)
Click here to see answer by jsmallt9(3296)

Question 377488: log_7(x+6)-log_7(x+2)=log_7x
Click here to see answer by jsmallt9(3296)

Question 377510: Convert the following logarithmic equation to the equivalent exponential equation. Use the caret (^) to enter exponents. y = ln x
Click here to see answer by Fombitz(13828)

Question 377511: Please slove 3^b=17

Click here to see answer by Fombitz(13828)

Question 377672: how do i solve this equation including the natural base e? The problem is:

e^x+4 = 1/e^2x. pls note, the "x+4" and the "2x" are the exponents of natural base e. I couldn't show that on this screen. I tried:
ln e^x+4 = ln 1/e^2x. i THINK that gives me:x+4 = ln (1/e^2x), but i don't know what to do nxt. Thx!!!
Click here to see answer by Fombitz(13828)

Question 377677: 16^x=32
Click here to see answer by Fombitz(13828)

Question 377677: 16^x=32
Click here to see answer by stanbon(57984)

Question 377677: 16^x=32
Click here to see answer by Alan3354(31538)

Question 377680: i need help with this problem: This is the model showing the percentage of Americans with heart disease who are "x" years old:
90/1+271e^-0.122x
At what age will the percentage of Americans with heart disease be 70%?
I'm thinking it works like this:
0.7 = 90/1+271e^-0.122x
ln 0.7= ln (90/1+271e^-0.122x)
NOW I AM STUCK!!!!! WHAT NOW???!!!! THX!!

Click here to see answer by Fombitz(13828)

Question 377689:
i need help with this problem: 2^2x+ 2^x - 12=0
This is what i tried, but i think it's wrong:
I tried to factor out: (2^x+6)(1^x-2), and now i am totally lost! pls help! Thx! Pls note: the "2x" and the "x" are exponents of the numbers 2. difficult to show that on this screen.

Click here to see answer by stanbon(57984)

Question 377694:
please help! i"m trying to solve:

log 2 (x-1) - log 2 (x+3) = log 2 (1/x)

This is what i tried, but i think it's wrong: used quotient rule like this: log 2 (x-1/x+3) = log 2 (1/x) OK! NOW WHAT???!!! I'm lost! :(

Click here to see answer by Fombitz(13828)

Question 377715: What is the domain of f(x) = log(x + 4) - 2?
x > -4
x ≥ -4
x > 4
All Real Numbers
Click here to see answer by Fombitz(13828)

Question 377746: I have two questions that I am struggling with.
1. Log x + log (x + 3)= 1 assume the log base is 10
2. log3 (2x-1)- log3 (x-4)=2
Thank you so much for your help!
Click here to see answer by Alan3354(31538)

Question 377862: i need help on solving for the logarithm:
e^(x+2)=4^(x)
Click here to see answer by josmiceli(9819)

Question 377993: Solve the exponential equation. Express the solution set in terms of natural logarithms:
8^3x = 2.2
Answer choices:
A. {ln 2.2 / 3 ln 8}
B. {2.2 ln 3 / ln 8}
C. {ln 2.2 / 8 ln 3}
D. {3 ln 2.2 / ln 8}
Thanks! (:
Click here to see answer by stanbon(57984)

Question 378044: express as a single logarithm. log x + log y + log z
Click here to see answer by robertb(4012)

Question 378052: Evalute
Log base x (x+3)=4
Click here to see answer by stanbon(57984)

Question 377925: Solve for X. 5^(2x-7) = 1/125
Click here to see answer by jsmallt9(3296)

Question 378049: Please advise on how to sketch the graph of f(x)=(2)^x-2 + 1. Show at least 2 points and dash in any asymptotes.
Click here to see answer by jsmallt9(3296)

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