Need to use your log rules log a +log b = log AB so the right side of the equation becomes log(4) (x-3)( x+5)and the left side is. log(4 ) (2x+1)
that means that (x-3)(x+5)= 2x+1
x^2 +2x -15 = 2x+1
x^2 -16=0
x=+/-4
now need to check for extraneous solutions . If you use -4 some of your expressions don’t exist since you cannot take the log of a negative number
so the only answer is x=4