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### Course: Geometry (FL B.E.S.T.) > Unit 9

Lesson 1: Area problem solving- Triangle missing side example
- Find missing length when given area of a triangle
- Finding height of a parallelogram
- Find missing length when given area of a parallelogram
- Scale factors and area
- Solving a scale drawing word problem
- Relate scale drawings to area

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# Finding height of a parallelogram

In this lesson, we learned that the area of a parallelogram equals the base times the height. Given an area of 24 units and a base of 6 units, we used this formula to find the missing height. The answer was 4 units. Isn't math fun?

## Want to join the conversation?

- What app are you using to draw and solve this equation(12 votes)
- He is using SmoothDraw 3 application and uses Wacom Bamboo Tablet (a device like a mouse that u can use to write. It's like writing on paper) to write in the application(28 votes)

- This is soooooo boring maybe if there is some no math and more games like coolmathgames(17 votes)
- Im not so sure about that. life is a nightmare(9 votes)
- Its awesome. Think happy!(1 vote)

- why do we even need to put the right angle box on the dotted line?(6 votes)
- 2 help us understand the steps of the question.(3 votes)

- I have no clue on this case and I am trying to solve a murder, pink panther singing out.(6 votes)
- Are you taking about the video(3 votes)

- Im so confused, why is there a 5?! No one uses it...

I kept on getting the excersises wrong because of the extra number. Somone please explain?(5 votes)- The 5 is supposed to mislead you. The reason why is because they are trying to see if you know what number to use. For that question, your supposed to find the height but the number 5 it not one of the numbers you use. Hope this helps!(4 votes)

- how do u wright with the mouse so smoothly(7 votes)
- they use a tablet, not a mouse(0 votes)

- the height to the first point is actually 5...i think it is at least.......................................(7 votes)
- well, if we know the length is 6 and that the area is 24, we can use the equation 24 divided by 6 and get the missing height of 4.(0 votes)

- help me plz I am stuck on this question.(5 votes)
- he just explained the answer?(3 votes)

- How everyone's day going?(6 votes)

## Video transcript

- [Lecturer] The parallelogram shown below has an area of 24 units
squared, or square units. Find the missing height. So, here's the parallelogram. This side has length six,
this side has length five. And we wanna find the missing height. And they gave us the area. So, pause this video and see if you can figure it out on your own. Well the key to solving this, is to realize how the area
relates to a base and height. An area of a parallelogram, area of a parallelogram is
going to be equal to the base, times the height. Now, what's the base in this scenario? Well, you could view this length, right over here as the base. Which is also going to be
the same as that length. In a parallelogram, opposite
sides have the same length. The parallel sides have the same length. So this going to be six. So our base is going to be six. And our height is what
we wanna figure out. So that, I will just
write as, this is the H that we're trying to figure out. And we know the area. The area is 24 square units. So there we go, we have
24 is equal to six. Is equal to...six times the height. So six times what, is equal to 24? Well six times four is equal to 24. So we know that H is going
to be equal to four units. H is equal to four units.