3log10-log(x+2) = 2 x=8?

The teacher says it = 8
But doesnt provide work
Can anyone help me?

1 Answer
May 22, 2018

3log10-log(x+2)=2

We can begin by evaluating the logarithmic value.

3(1)-log(x+2)=2

3-log(x+2)=2

We then need to isolate the variable.

log(x+2)=1

Next, we simplify the logarithm by converting it to exponent form.

log_bx=y becomes b^y=x

In this case, b=10, the standard base for logarithms if not stated otherwise. Also, x=x+2 and y=1.

log(x+2)=1 becomes 10^1=x+2

10=x+2

8=x

We can check the answer x=8 and plug this value into the equation.

3log10-log(8+2)=2

3log10-log10=2

2log10=2

To isolate the logarithm, we need to further simplify.

(cancel(2)log10)/cancel(2)=cancel(2)/cancel(2)

log10=1

1=1

Therefore, x=8 works.