lnx = ln3 - ln(x+5)?

2 ⤊

lnx = ln3 - ln(x+5)?

find x.
thanks :)

2007-10-28 18:29:23 · 3 answers · asked by candy 3 in Science & Mathematics ➔ Mathematics

3 answers

lnx=ln3-ln(x+5)
{log(A/B)=log A-log B
}
using the above formula we have
lnx=ln(3/(x+5))
x=3/(x+5)
x^2+5x-3=0
now solve the equation us ing quadratic formula.

2007-10-28 18:36:27 · answer #1 · answered by Ashwin 2 · 1⤊ 1⤋

ln x = ln (3 / (x + 5) )
x = 3 / (x + 5)
xÂ² + 5x - 3 = 0
x = [- 5 Â±â(25 + 12) ] / 2
x = [- 5 Â± â(37) ] / 2

2007-10-29 11:18:52 · answer #2 · answered by Como 7 · 1⤊ 0⤋

raise everything to power e so you get
x = 3 -(x+5)

so

2x = -2

so

x =-1

2007-10-29 01:35:31 · answer #3 · answered by Scotty 3 · 0⤊ 1⤋