# Tutor.com Linear Equations Session

##### Feb. 13, 2013

Session Transcript - Math - Algebra, 1/27/2013 9:07PM - Tutor.comSession Date: 1/27/2013 9:07PM
Length: 42 minute(s)
Subject: Math - Algebra

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

Kyle (Customer)
[00:00:00] I don't remember this [ File > http://LHH.Tutor.com/SharedSessionFiles/f650903b-ae8c-4ea8-ac08-d2ed36663862_picture049.jpg ]

John P (Tutor)
[00:00:10] Welcome to Tutor.com ! Let's get started.
[00:00:21] i'm going to take a look at the file, one moment
[00:00:48] ok, i see the problem now
[00:00:59] so you need to write an equation first

Kyle (Customer)
[00:01:10] yea

John P (Tutor)
[00:01:27] any idea how to start on that?
[00:01:50] if you're not sure, that's ok

Kyle (Customer)
[00:02:20] y= 700+ .08X

John P (Tutor)
[00:02:32] ok, yes, that looks good
[00:02:43] ok, so part B
[00:03:18] how would you figure out how many dollars of insurance he must sell to earn \$2000
[00:03:19] ?

Kyle (Customer)
[00:03:58] x= 104 policies

John P (Tutor)
[00:04:38] you plugged in 2000 for y?
[00:04:50] to figure that out

Kyle (Customer)
[00:04:48] yea

John P (Tutor)
[00:05:26] i don't think \$104 in insurance policies is enough
[00:05:52] that's what your equation looked like?

Kyle (Customer)
[00:06:48] i havent been able to see anything on rhe boARD

John P (Tutor)
[00:07:06] oh, ok, im sorry
[00:07:15] let me type it in the textbox
[00:07:27] 2000=700 + .08x
[00:07:34] is that the equation you used?
[00:07:51] to figure out how much money in insurance policies he would need to sell
[00:07:58] to earn \$2000

Kyle (Customer)
[00:08:04] the same oe
[00:08:08] one

John P (Tutor)
[00:08:17] ok
[00:08:26] what did you do first to solve that equation?
[00:08:32] what was your first step?

Kyle (Customer)
[00:09:02] -700

John P (Tutor)
[00:09:17] ok
[00:09:53] so that should have given you 1300=.08x
[00:10:14] and then what would come next?

Kyle (Customer)
[00:10:13] yea

John P (Tutor)
[00:10:33] and then what do you do to solve for x?

Kyle (Customer)
[00:10:32] /.08

John P (Tutor)
[00:10:45] correct
[00:10:48] and what do you get?

Kyle (Customer)
[00:10:49] idk

John P (Tutor)
[00:11:03] do you have a calculator?

Kyle (Customer)
[00:11:00] 16250

John P (Tutor)
[00:11:15] that's correct!
[00:11:16] :)

Kyle (Customer)
[00:11:10] yea

John P (Tutor)
[00:11:41] ok, so that was part b
[00:11:49] what do you get for part c?
[00:14:09] just making sure you are still there, im guessing maybe you are trying to solve part c

Kyle (Customer)
[00:14:32] 8700

John P (Tutor)
[00:15:11] actually i got \$80700
[00:15:21] i don't know if you missed a zero somewhere

Kyle (Customer)
[00:16:26] did u multiply by .8 instead of .08?

John P (Tutor)
[00:16:49] no, i don't think so
[00:17:03] .08 times 1,000,000 is 80,000

Kyle (Customer)
[00:17:28] yup i did it wromg

John P (Tutor)
[00:17:41] ok
[00:17:50] all set with that one?

Kyle (Customer)
[00:17:58] yup!

John P (Tutor)
[00:18:34] now, you are supposed to graph this?
[00:18:47] the numbers are going to be a little tricky to graph

Kyle (Customer)
[00:18:40] yup

John P (Tutor)
[00:19:10] ok, so i put it into y=mx+b form on the whiteboard
[00:19:24] what would the y-intercept be on the graph?
[00:20:27] ?

Kyle (Customer)
[00:20:58] i cant see it and i dont think we use it?

John P (Tutor)
[00:21:17] oh sorry, i forgot
[00:21:26] y=.08x+700
[00:21:50] so that is what the equation would look like in slope intercept form, y=mx+b
[00:22:13] you are supposed to do part d, correct?

Kyle (Customer)
[00:22:22] yea

John P (Tutor)
[00:22:45] and you're familiar with slope intercept form?

Kyle (Customer)
[00:22:56] kinda

John P (Tutor)
[00:23:07] graphing by identifying the y-intercept and slope
[00:23:25] what is the y-intercept on that equation?

Kyle (Customer)
[00:23:56] 700

John P (Tutor)
[00:24:04] right
[00:24:08] and what is the slope?

Kyle (Customer)
[00:24:16] .08

John P (Tutor)
[00:24:44] and it does ask you for the domain and range
[00:24:48] what is the domain?

Kyle (Customer)
[00:24:50] yu
[00:24:55] d=x

John P (Tutor)
[00:25:01] are there any x-values that will not be part of the graph?

Kyle (Customer)
[00:24:58] r=y

John P (Tutor)
[00:25:08] yes, that's right
[00:25:23] so are there any x-values that aren't possible for this problem?

Kyle (Customer)
[00:25:58] no

John P (Tutor)
[00:26:05] think about what the x means on this problem
[00:26:12] what does the x mean?

Kyle (Customer)
[00:26:16] x

John P (Tutor)
[00:26:40] what does the x mean for this word problem? what does that variable represent?

Kyle (Customer)
[00:27:06] 16250

John P (Tutor)
[00:27:39] i don't mean specifically, i mean for the problem
[00:27:54] what type of value are you plugging in for x?
[00:28:03] or if you need to find x, what are you finding?

Kyle (Customer)
[00:28:11] idk

John P (Tutor)
[00:28:51] isn't x the amount of dollars in insurance policies that the person is selling?

Kyle (Customer)
[00:29:04] yea

John P (Tutor)
[00:29:22] so are there any types of numbers that x couldn't be?

Kyle (Customer)
[00:29:51] idfk

John P (Tutor)
[00:30:30] i'm sorry if you're getting frustrated by those questions, i'm trying to help you figure out what the domain is for this problem

Kyle (Customer)
[00:30:55] ok, sorry :)
[00:31:04] i m focused

John P (Tutor)
[00:31:18] i'll explain where i am going with this - x can't be a negative number because there is no way that the person would sell a negative number of dollars of insurance
[00:31:32] so the domain would have to be x is greater than or equal to 0
[00:31:39] does that make sense?

Kyle (Customer)
[00:31:44] yea

John P (Tutor)
[00:32:07] ok
[00:32:24] and for the range, the y-intercept is 700
[00:32:38] that means that the person earns \$700 no matter what

Kyle (Customer)
[00:32:54] ok

John P (Tutor)
[00:33:00] and could make more money than that if they sell insurance, but couldn't possibly make less
[00:33:05] so the range is...
[00:33:13] y is greater than or equal to 700
[00:33:17] ok?

Kyle (Customer)
[00:34:28] k can you right it on the board and than i can see if i did it right when i exit?

John P (Tutor)
[00:35:19] is that ok like that?

Kyle (Customer)
[00:36:08] i cant see it? is it filled in with the 700 and 0 and whatever

John P (Tutor)
[00:37:17] i wrote what the domain and range are and the equation written in two rearranged orders, im not sure if you can see that stuff
[00:37:23] or if you are looking for more

Kyle (Customer)
[00:38:22] is the graph, graphed?
[00:38:45] because i cant see nothin on the board

John P (Tutor)
[00:38:59] i didn't actually do the graph, no, i just went over what the y-intercept would be and the slope
[00:40:07] it might actually be a little easier to sketch the graph by hand rather than try to put it up on here
[00:41:02] ok?
[00:41:07] i hope you understand

Kyle (Customer)
[00:41:19] no but bye

John P (Tutor)
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