# algebra

Ln(x+3)- Ln(x-5)=Ln7

1. 👍 0
2. 👎 0
3. 👁 149
1. recall that lna-lnb = ln a/b, so

ln (x+3)/(x-5) = ln 7
(x+3)/(x-5) = 7
x+3 = 7x-35
x = 19/3

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Pre-calculus: Logarithms

ln56/ln7=ln8. Is this true or is this false? How can I find this out?

2. ### Calculus

would the derivative of f(x)=(7^x)(x^7) be f'(x)=(7^x ln7) (7x^6)?

3. ### math

Suppose that ln7 = a and ln8 = b. Use properties of logarithms to write this logarithm in terms of a and b. ln root5(56)

4. ### Pre Cal/Logarithism

given that f(x)=11^x, find x when f(x)=7 a) x=Ln(7/11) b) x=Ln7/Ln11 c) x= 7/11 d) x= ll sub 7 11

1. ### Logarithmic Function help

Ok, I was getting all my answers right until I stumbled on this one: 5e^0.2x=7 This is what I was doing: 5e^0.2x=7 5lne^0.2x=ln7 5*0.2x=ln7 0.2x=(ln7/5) ??? The answer is 5ln(7/5) but i do not know how they derived to this. Thank

2. ### algebra

I am to solve ln(x+3)-ln(x-5)=ln7

3. ### algebra

I need some help with ln 's I am trying to solve : ln(x+3)- ln(x-5)= ln7 do I: ln (x+3)/(x-5)= ln 7 ?

4. ### Precal

solve for x 7^x/2=5^1-x what i have so far is: (x/2)ln7=(1-x)ln5 im not sure where to go from there

1. ### calculus

can anyone help me simplify this problem? ln(x-3)(x+2)-ln(x+2)^2-ln7

2. ### Math

ln(y-9)-ln7=x+lnx Thank you sooo much for helping:))))

3. ### Calculator Question

how do I input ln7/ln2/5600 correctly in my calculator to get 2900 as my answer?