more problems I dont get.

**kenny87** · April 26th 2010, 08:14 PM

more problems I can't understand

9^x+2 = 27^-3

I get that 3 will go into both of them but am lost after that, notes don't help

instructions are to solve each exponential equation. Round to 2 decimal places.

and another logarithm

Log (xy^2/Z^4)
Z

edit: Z should be right after/underneath "log" and before the (.

**pickslides** · April 26th 2010, 08:37 PM

Originally Posted by kenny87

more problems I can't understand

9^x+2 = 27^-3

$9^{x+2} = 27^{-3}$

$(3^2)^{x+2} = (3^3)^{-3}$

$3^{2(x+2)} = 3^{3\times -3}$

$2(x+2) = 3\times -3$

Can you finish this?

**lightbanders** · April 26th 2010, 08:43 PM

I guess the problem says 9^(X+2)=27^-3. In this case, (3^2)^(X+2)=(3^3)^-3 and get 3^(2X+4)=3^-9 and from that point you can go on.

**pickslides** · April 26th 2010, 08:47 PM

Originally Posted by kenny87

and another logarithm

Log (xy^2/Z^4)
Z

edit: Z should be right after/underneath "log" and before the (.

What are you supposed to do with this expression?

$<br /> \log_z \frac{xy^2}{z^4} = \log_z xy^2- \log_z z^4 = \log_z xy^2- 4\log_z z = \log_z xy^2- 4\times 1= \log_z xy^2- 4<br />$

**kenny87** · April 26th 2010, 10:05 PM

says to expand or condense expression as much as possible.

**kenny87** · April 26th 2010, 10:11 PM

more problems I can't understand

9^x+2 = 27^-3

my bad, problem is 9^x+2 = 27^ -x

I must have been looking two places at once or something. I figured that one out though looking at what you did.

It was in the first section of my notes, one more though

e^5x =77

I have one example dealing with E but it has E on both sides so not sure what to do here. Hopefully this is my last question, thanks for the help.