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Lesson 2: Areas of triangles

# Triangle missing side example

Dive into the world of triangles! Learn how to find a missing piece using just the area and height. Apply this knowledge to solve puzzles and explore the magic hidden in these three-sided shapes. Join the triangle adventure!

## Want to join the conversation?

• So, the 11 is useless? For this problem?
• Yes you are correct that the 11 would be useless for this particular problem. An important skill in mathematics is separating useful information from useless information. Sometimes useless information is included on math test problems to test the students' ability to separate useful information from useless information. The useless information is sometimes used to create wrong answer choices (traps) on multiple choice test questions.
• so confusing cant you just do b times h divided by 2
• Yes u can, but only if you know the base and height. This skill is about figuring out the missing base/height when you are given the base/height and the area of the triangle

As an example, let's say the base was 10 and the area was 300. We need to find the missing height. The formula to figuring out the area of a triangle is
(b * h) / 2. Therefore, (10 * h) / 2 = 300, and
(10 * h) = 600. 600 / 10 is 60, so h is 60, as
(10 * 60) / 2 = 300 and (10 * 60) = 600
• I don't understand why math is so hard
• The more you understand math, the more you will like it. Trust me, in the beggining, I hated math, because I didn't understand it and thought it was too hard. But now, I understand it better, and I enjoy doing math now.
• So I paused the video and tried to do it myself, I got the answer right, but I did it differently. I just wanted to make sure it would always work in a situation like this. So I divided 75 by 10 and got 7.5, knowing that this is actually 1/2 the base, multiplied this by 2 and got 15, sounds like a lot, but only took me about 1 minute to do compared to your way, which is why I wanted to know if it was a correct way of doing it.
• I agree, this method is quite efficient. I recommend doing this if your stuck on doing the equations.
• Why is 11 there if we don't need it? They're scamming us, that's illegal in my book.
• They put it there as mostly a set up to see if you listened or not I'm guessing
• So to find the missing side its just the area divided by half of the hight
• Why did they just put the 11 there to distract you?
• Questions/Teachers love to confuse you, the distractions make you confused and get the question wrong. Hope you got the answer correctly!