# Tutor.com Exponential and Logarithmic Functions Session

##### May. 26, 2012

Session Transcript - Math - Algebra II, 5/16/2012 9:00PM - Tutor.comSession Date: 5/16/2012 9:00PM
Length: 24.9 minute(s)
Subject: Math - Algebra II

System Message
[00:00:00] *** Please note: All sessions are recorded for quality control. ***

Kayla (Customer)
[00:00:00] 93 [ File > http://www.tutor.com/SharedSessionFiles/7d0417a8-b7c6-4b7f-bc12-0602e6bf76e3_Math.jpeg ]

Charles C (Tutor)
[00:00:12] Welcome to Tutor.com ! My name is Charlie.

Kayla (Customer)
[00:00:14] hi. can you help me do 93?

Charles C (Tutor)
[00:00:52] Sure. Did you have some work done on it already?

Kayla (Customer)
[00:00:56] no

Charles C (Tutor)
[00:01:12] OK. Let's take a look.
[00:01:47] So, do you have an idea of how to start the problem?

Kayla (Customer)
[00:01:56] swap x&y

Charles C (Tutor)
[00:02:25] That's a good start! I'll start writing it up.
[00:03:24] Look ok so far?

Kayla (Customer)
[00:03:30] yes

Charles C (Tutor)
[00:04:01] All right. So any ideas for a next step?

Kayla (Customer)
[00:04:07] nope

Charles C (Tutor)
[00:04:37] OK. What we need to do here is solve for y.
[00:04:48] Does that sound right to you?

Kayla (Customer)
[00:05:09] yes

Charles C (Tutor)
[00:05:52] Good! So right now, we've got the y stuck inside the log_2, and we need to do something to get it out.
[00:08:13] Have you seen the trick of raising some number to a power involving the log function to get rid of the log?

Kayla (Customer)
[00:08:25] yes
[00:08:49] so we put a big 2 under everything

Charles C (Tutor)
[00:09:02] That's right!
[00:10:04] Since both sides of the equation are equal to each other, if we take 2^(left side), that's equal to 2^(right side), and that also gets rid of the log_2.

Kayla (Customer)
[00:11:00] y=x-10

Charles C (Tutor)
[00:12:00] Close! We're still going to be stuck with the x as the exponent of the 2, but the right side does simplify to y+10, and we subtract the 10.
[00:12:44] Does that make sense? Any questions on any of that?

Kayla (Customer)
[00:12:53] no

Charles C (Tutor)
[00:13:21] Was there a similar one you wanted to try, or are you okay on that now?

Kayla (Customer)
[00:13:36] the next one?

Charles C (Tutor)
[00:14:44] OK. Why don't you put that one up and work through it, and I'll help you out if you need it. Sound ok?

Kayla (Customer)
[00:15:29] File Shared > Math.jpeg
[00:15:36] 94

Charles C (Tutor)
[00:16:25] OK. So what's your first step?

Kayla (Customer)
[00:16:36] swap x&y

Charles C (Tutor)
[00:16:46] Good.
[00:17:28] What next?

Kayla (Customer)
[00:17:58] giant 5?

Charles C (Tutor)
[00:18:19] Let me think a second...
[00:19:19] That will work ok. It might be easier to divide by the -7 first, but either way should work out.

Kayla (Customer)
[00:19:39] okay, then well divide

Charles C (Tutor)
[00:19:50] OK.
[00:20:31] And now giant 5...
[00:21:34] Does that all make sense?

Kayla (Customer)
[00:21:43] yea

Charles C (Tutor)
[00:22:34] Cool!
[00:23:34] Now that we've looked at those, I should go on and help some other students.
[00:24:06] You understand everything we went over ok?