About this video
The video finds the area of a triangle with base 18 and height 6. Using area = 1/2 x base x height, it halves 18 to get 9 and multiplies by 6 to get 54 square units.
You'll be able to
- identify the base and height of a triangle.
- use area = 1/2 x base x height.
- simplify the calculation by halving first.
Key words
- base
- The side of the triangle you measure the height to.
- height
- The straight-up distance from the base to the opposite corner.
- square units
- The units for measuring area.
Transcript
- [Instructor] What is the area of the triangle? And they're talking about this triangle here. And like always, pause this video and see if you can figure it out on your own. All right, now let's work through it together. So we know that the area of a triangle is going to be equal to 1/2 times our base times our height.
Let me do the height in a different color. Times, times our height. So, what is the length of our base in this scenario? Well, the base is this 18 right over here. Let me highlight it. This length right over here is our base. So the base is 18. And what is the height?
Well, the height, we see, is six. They give it to us. They don't always give it to you, but in this example they do. So the height is, the height... The height is, I'm having trouble with my pen, is six. So now we just have to compute what 1/2 times 18 times six is.
Well, let's think about this a little bit. Well, 1/2 times 18 is nine. Nine times six is equal to what? Nine times six is equal to 54. And we are done. This is 54 square units.
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