Question

solve:
log x + log (x+3) = log 10

I am stuck...
log (x^2+3x) = log 10
x^2+3x=10
from here i just get weird numbers. helppp

Answer 1

answer in the back says it should equal 2...

Answer 2

It is true that log(x) + log(x+3) = log(x*(x+3))
\[x^2 +3x-10=0\]
\[x^2+5x-2x-10=0\]

Answer 3

i always forget that whole set one side equal to zero....let me see if i can get it from there

Answer 4

FOIL and the domain of the log function and you got it. Cheers.