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## Geometry (all content)

# Drawing a trapezoid on the coordinate plane example

Watch Sal solve an example problem where he draws an isosceles trapezoid on the coordinate plane.

## Want to join the conversation?

- Does anyone have an easier way of remembering where the quadrants are?(5 votes)
- You start with the x axis. Just think of it as playing basketball, you run straight then jump you don't jump then run. I hope this helped! PLEASE GIVE THIS A THUMBS UP!

:)(6 votes)

- whenever I do the practice task, i get them right but the practice task doesn't finish,

what can I do?(1 vote)- That is a bug! Whenever that happens, click on the report a problem and then tell them your problem.(4 votes)

- But in the practice this concept there is not the video said could you help me?(2 votes)
- How do you do it because i can't(1 vote)
- sometimes i answer a question but it doesn't let me click answer. also, sometimes (alot of times) the graph doesn't pop up on my question. what do i do? even when i report it nothing happens, now i'm stuck on this question!(1 vote)
- how does the coordinate plane apply in our real life?(1 vote)
- It actually has no effect on life. They try to make you feel better. I am already depressed with seeing a whale shark get cut up while it was alive. Rest his cut up soul(1 vote)

- the video won't load can't understand!(1 vote)
- I am having trouble with this stupid problem witch im getting right but it says i dont get it right(1 vote)
- This video DOESN'T help AT ALL for the problem i'm on and every single question I get and I click on one of the videos to watch it's always the EXACT SAME VIDEO! EVERY.SINGLE.TIME. From now on, for every question, they need to have a video that has the exact same question that the student gets for every single question because,ALL of these questions are different and using the exact same one for every single different question DOESN'T HELP! These questions just don't make sense to me. I know this was long and sorry not sorry. PLEASE LIKE THIS COMMENT IF YOU AGREE WITH ME!(1 vote)
- That is a bug! Whenever that happens, click on the report a problem and then tell them your problem.(1 vote)

- I don't understand how to do the FIFA field question. Does anyone know how to help me?(1 vote)

## Video transcript

- "Click on the graph to
draw an isosceles trapezoid "with vertices at negative two comma eight "and negative four comma negative one. "Another vertex at three comma eight "and a base nine units long "that is parallel to the x-axis." All right, let's see if we can do this. So we could just start
plotting these vertices. So negative two comma eight. X is negative two, y is eight. That's that point right over there. The next one is x is negative
four, y is negative one. x is negative four, y is negative one and that's nice. They connect the dots for us. Then they say three comma eight. So three comma eight. It's gonna be right up here. Now I think when I click it, it's going to try to draw a line between this point and this point which isn't what we want. This is a trapezoid,
an isosceles trapezoid. I actually want to
connect three comma eight to this point right over here
to negative two comma eight. So let me see what happens. Yep, yeah, that's not
what I wanted to happen. So let me actually delete this. Let me delete here. I'm actually gonna plot this one first. Then I'm going to plot this one, then I'm going to plot this
one and then I'm going to see where I need to put this other one. So let me delete all of these. We move these all to the trash. So move them all to the trash. And so let me start over. So I'm going to start, that looks like some type
of a bug but let's see. Let's hopefully it still works. Let's plot three comma eight first. Three comma eight. That's that point. Then we're going to plot
negative two comma eight. Negative two comma eight. This is the top of our
isosceles trapezoid. It's nice to give us the length that has, the length of this top is five. And then, now you can do
negative four comma negative one. Negative four comma negative one is this point right over here. All right, now this is
looking like a trapezoid. And now a base nine units long that is parallel to the x-axis. So base, it's nine units long and it's parallel to the x-axis. We just have to move to
the right, nine units. One, two, three, four, five, six, seven, eight, nine units. And then we just move back up. And it does look like
we have got ourselves an isosceles trapezoid. What is an isosceles trapezoid mean? It means that these two sides, the non top or non bottom or non base sides are going to be equal. And we see that this side
over here is equal to that and that this top is, you can kind of view, it's in the middle. That's one way to think about it. So I like this isosceles trapezoid. So let's check our answer. Make sure that we've drawn it right. Yeah, we did good.