I'm studying for my precalc exam and have completed 42 practice problems. I have 3 I need to answer that I can't. Please help. What is the base of the function G(x) = log subscript b x if it's graph has points (16,4)? Using the properties of logarithms how do I rewrite log subscript 5 2/3 + log subscript 5 9/10? What is the value of log subscript 2 (8 1/2 )? Thank you so much my brain is about to explode with the amount of math I've done in the past two days.

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<<What is the base of the function
G(x) = log subscript b x
if it's graph has points (16,4)?>>
Ask yourself this:
What number to the 16th power is 4? The answer is 1.09051. That is the base b of the G(x) log function in this case.

<<Using the properties of logarithms how do I rewrite log subscript 5 2/3 + log subscript 5 9/10?>>
log(sub5) 2/3 + log(sub5) 9/10?>>
= log(sub5) [(2/3)*(9/10)]
= log(sub5) 3/5

<<What is the value of
log(sub2) (8 1/2 )?
2^x = 8.5
x log 2 = log 8.5 (use any base)
x = 3.087

I can't remember how to create a system of equations using one cooridnate plain point can anyone help me???