SAT prep: test 1 section3 part 1 Video

By: Guest More than a year ago

This is really smart! You should do more than math though.

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SAT prep: test 1 section3 part 1

Good morning. Well today is I hope it’s an exiting day. It kind of cut and we were just going to start a new set of lectures. But what we’re going to do is I’m not sure it’s going to work through just a bunch of SAT problems. So, D is like SAT prep for free or for this interview, or copying for free. I hope neither of them sue me for using their names. But anyway, what I want you to do is if you haven’t already, I want you to buy this book right here, “The Official SAT Study Guide”. You’ll see it in the bookstore and I hope I’m not doing any kind of copyright infringement. I’m not a lawyer so I don’t know all the rules, but I’m pretty sure as long as I give them credit and that you know that all of the problems we’re going to be doing are from their book and I’m just going to work through them, hopefully that shouldn’t be something that’s wrong. But anyway, as often as possible, I’m going to work through all of the problems in each of the math sections. So, the best thing for you to do is for the same section, do them ahead of time for yourself, try to do as many as you can, score your test and then whichever problems you don ‘t know, you could just watch on Khan Academy and hopefully, understand them or reunderstand them. So with that said, let’s get started. So, I’m using this book right here, Official SAT Study Guide and I am starting on page 395. This is a section three I believe of the first math section and this is page 395. So, sometimes I write the whole problem, sometimes I won’t. I'm going to assume that you have the textbook so that said, let’s begin. So the first problem, problem number one. It says, “If 2x+3=9, then what is 4x-3? Well, this is just a very basic algebra problem. If you don’t remember how to do this, you should probably review the level one and level two linear equations lectures that I have in the algebra playlist. But the way we do this, we could solve for x here. So, we can just subtract three from both sides, 2x+3-3 so you get a zero here is equal to six and x=3. And so, if you do 4x-3, that’s 4*3-3 and that’s 12-3 and that also equals nine. You could have kind of done this a little bit faster but this is a little one way that you would make sure that you’ve got the right answer. And on this test, it’s b9. Number two. There are eight sections of seats in an auditorium. There are eight sections of seats in an auditorium. Each section contains a 150 seats but no more than 250 seats, at least a 150 but no more than 200 so each section—so, if we say S is seats. Let me say S is seat so seats are greater than or equal to 150 and less than or equal to 200. This is kind of seats per section. I hope I’m not confusing you, seats per section. Which of the following could be the number of seats in this auditorium? So, before I even look at the choices, I mean you could put the choices. You just have to figure out. Well, what’s the minimum number of seats in this auditorium? Well, the minimum number is if every section only has 150 seats, right? So, the minimum number is 8*150, eight sections, each of them having a 150 seats because this is the case in which every section has a smallest number of seats. So, 150*8, 0, 40, 1*8=8+4=12. So, this is the minimum number of seats in the auditorium. And then the maximum number would be if we assume every section had the maximum number of seats, so that would be 200*8=1600. So, we know that seats is going to be greater than or equal to this and less than or equal to this. And what choice falls under that range? Choice A doesn’t, it’s 800. Choice B doesn’t, choice C doesn’t, choice D 1300 does into that range and we know that choice E doesn’t fit into that range so we’re done. It’s D, 1300 seats is a possibility. And we turn the page and we have a graphical problem. Okay. Note, figure not drawn the scale in the figure above. Okay. Let me draw this. I will use sky blue. So, let me draw that line. So, they have a line like that and they have another line that goes up and down like that. And then, they had a bunch of points so let me draw those points. So we have point A, point B, point C, point D, point E, and they called this horizontal line. They are calling this line L and X. In the figure above, XC is perpendicular to L, so this XC is perpendicular line L. So, we know that this is a 90-degree angle. Which of the following line segments has the greatest length on in the figure, they also tell you the measurements of the different lengths. So, let’s say from A to be B is three, from B to C is two, C to D is three, D to E is one, and from C to X is eight. Which of the following line segments that are not shown has the greatest length? The first choice, choice A is line segment XA, choice B is line segment XB, choice C is line segment XC, choice D is line segment XD, and then choice E is line segment XE. So, which of the following segments has the greatest length? So, if you just eyeballing it, you’ll know that this XB is definitely going to be shorter than XA. Why is that? Because if you used—well, one you could just eyeball it, I know it’s not drawn in the scale but you definitely know that this length, this base is longer than this base right here. So, we know it’s not going to be XB. We know XB is shorter than definitely XA so we can cross that one out. Then what we don’t know and we could do the same thing on the other side of this perpendicular line. We know that XD is shorter than XE, right? Same reasons because we know this base is longer. And if you use a Pythagorean Theorem, you would know that this hypotenuse is going to be longer than this one. And you can review Pythagorean Theorem and get familiar with the triangles if that doesn’t make a lot of sense, but that tells us that it’s definitely not going to be XD. And we also know it’s not going to be XC. This is the shortest of all of them and you could eyeball that. So, it’s either going to be XE or XL. And the way we figure out which one has the longer hypotenuse is we say they all have the same height. So, which one has a longer base? So, this one has a base, this triangle right here if we say this triangle has a base of four and this triangle here has a base of five. So, this hypotenuse will be the longest. XA is the answer. I’ll see you in the next video.

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Good morning. Well today is I hope it’s an exiting day. It kind of cut and we were just going to start a new set of lectures. But what we’re going to do is I’m not sure it’s going to work through just a bunch of SAT problems. So, D is like SAT prep for free or for this interview, or copying for free. I hope neither of them sue me for using their names. But anyway, what I want you to do is if you haven’t already, I want you to buy this book right here, “The Official SAT Study Guide”. You’ll see it in the bookstore and I hope I’m not doing any kind of copyright infringement. I’m not a lawyer so I don’t know all the rules, but I’m pretty sure as long as I give them credit and that you know that all of the problems we’re going to be doing are from their book and I’m just going to work through them, hopefully that shouldn’t be something that’s wrong. But anyway, as often as possible, I’m going to work through all of the problems in each of the math sections. So, the best thing for you to do is for the same section, do them ahead of time for yourself, try to do as many as you can, score your test and then whichever problems you don ‘t know, you could just watch on Khan Academy and hopefully, understand them or reunderstand them.

So with that said, let’s get started. So, I’m using this book right here, Official SAT Study Guide and I am starting on page 395. This is a section three I believe of the first math section and this is page 395. So, sometimes I write the whole problem, sometimes I won’t. I'm going to assume that you have the textbook so that said, let’s begin.

So the first problem, problem number one. It says, “If 2x+3=9, then what is 4x-3? Well, this is just a very basic algebra problem. If you don’t remember how to do this, you should probably review the level one and level two linear equations lectures that I have in the algebra playlist. But the way we do this, we could solve for x here. So, we can just subtract three from both sides, 2x+3-3 so you get a zero here is equal to six and x=3. And so, if you do 4x-3, that’s 4*3-3 and that’s 12-3 and that also equals nine. You could have kind of done this a little bit faster but this is a little one way that you would make sure that you’ve got the right answer. And on this test, it’s b9.

Number two. There are eight sections of seats in an auditorium. There are eight sections of seats in an auditorium. Each section contains a 150 seats but no more than 250 seats, at least a 150 but no more than 200 so each section—so, if we say S is seats. Let me say S is seat so seats are greater than or equal to 150 and less than or equal to 200. This is kind of seats per section. I hope I’m not confusing you, seats per section. Which of the following could be the number of seats in this auditorium? So, before I even look at the choices, I mean you could put the choices. You just have to figure out. Well, what’s the minimum number of seats in this auditorium? Well, the minimum number is if every section only has 150 seats, right? So, the minimum number is 8*150, eight sections, each of them having a 150 seats because this is the case in which every section has a smallest number of seats. So, 150*8, 0, 40, 1*8=8+4=12. So, this is the minimum number of seats in the auditorium. And then the maximum number would be if we assume every section had the maximum number of seats, so that would be 200*8=1600. So, we know that seats is going to be greater than or equal to this and less than or equal to this.

And what choice falls under that range? Choice A doesn’t, it’s 800. Choice B doesn’t, choice C doesn’t, choice D 1300 does into that range and we know that choice E doesn’t fit into that range so we’re done. It’s D, 1300 seats is a possibility. And we turn the page and we have a graphical problem. Okay. Note, figure not drawn the scale in the figure above. Okay. Let me draw this. I will use sky blue. So, let me draw that line. So, they have a line like that and they have another line that goes up and down like that. And then, they had a bunch of points so let me draw those points. So we have point A, point B, point C, point D, point E, and they called this horizontal line. They are calling this line L and X. In the figure above, XC is perpendicular to L, so this XC is perpendicular line L. So, we know that this is a 90-degree angle.

Which of the following line segments has the greatest length on in the figure, they also tell you the measurements of the different lengths. So, let’s say from A to be B is three, from B to C is two, C to D is three, D to E is one, and from C to X is eight. Which of the following line segments that are not shown has the greatest length? The first choice, choice A is line segment XA, choice B is line segment XB, choice C is line segment XC, choice D is line segment XD, and then choice E is line segment XE. So, which of the following segments has the greatest length?

So, if you just eyeballing it, you’ll know that this XB is definitely going to be shorter than XA. Why is that? Because if you used—well, one you could just eyeball it, I know it’s not drawn in the scale but you definitely know that this length, this base is longer than this base right here. So, we know it’s not going to be XB. We know XB is shorter than definitely XA so we can cross that one out. Then what we don’t know and we could do the same thing on the other side of this perpendicular line. We know that XD is shorter than XE, right? Same reasons because we know this base is longer. And if you use a Pythagorean Theorem, you would know that this hypotenuse is going to be longer than this one. And you can review Pythagorean Theorem and get familiar with the triangles if that doesn’t make a lot of sense, but that tells us that it’s definitely not going to be XD. And we also know it’s not going to be XC. This is the shortest of all of them and you could eyeball that.

So, it’s either going to be XE or XL. And the way we figure out which one has the longer hypotenuse is we say they all have the same height. So, which one has a longer base? So, this one has a base, this triangle right here if we say this triangle has a base of four and this triangle here has a base of five. So, this hypotenuse will be the longest. XA is the answer. I’ll see you in the next video.

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