log (x+5) = 2- log (2x).
I
believe that you need to determine the values of x that satisfies the
equation.
We will use logarithm properties to solve for
x.
First we will add log 2x to both
sides.
==> log (x+ 5) + log (2x) =
2
Now we know that log a + log b= log
a*b.
==> log (x+5)*2x =
2
==> log ( 2x^2 +10x) =
2
Now we will rewrite into the exponent
form.
==> 2x^2 + 10x =
10^2
==> 2x^2 + 10x =
100
==> 2x^2 + 10 x -100 =
0
Now we will divide by
2.
==> x^2 + 5x -50 =
0
Now we will
factor.
==> (x+10) (x-5) =
0
==> x1= -10 ==> Not valid because log ca
not be negative.)
==> x2=
5
Let us check .
==>
log (5+5) = 2 - log 2*5
==> log 10 = 2- log
10
==> 1 =
2-1
==> 1 = 1
Then the
answer is valid
==> Then the answer is
x= 5.
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