Do we need math in our life mostly people dont use it in the modern world only high tec jobs do

math is the foundation of everything. think about it you need to know how many dollar socks you can get, the amount of tip to leave, or even what your Christmas gifts will cost.

This is very helpful! Does this work for all triangles?

_Yes! it works for all triangles!_

why do you want to find area of a triangle

why...... why have a triangular room.....WHYYYYY

do you have to divide it by two

if you dont you are technically doing normal rectangle area

the triangles are hard to do sometimes.

yea but youjust have to do it a ot

is there any other formula which can be used to find an area of a triangle

1) abc/4R (R is radius of circumscribed circle) 2) r/2×(a+b+c) (r is radius of inscribed circle) 3) If you know the coordinates of the three points, use the shoelace formula 1/2×|x₁y₂+x₂y₃+x₃y₁-x₂y₁-x₃y₂-x₁y₃|

I will accept all the help I can get because I can really make use of it.

Use the formula base (usually the bottom part of the triangle) times the height (the distance from the very top point of the triangle down to the middle of the base) divided by 2. Usually the height is represented as a dotted line.

Is math really “that important?” That’s why god invented calculators isn’t it.

yes cause without math millions of things wouldn't be invented just like khan academy. computers, phones, tablets, buildings, and even parks wouldnt be here if it weren't for math, that's why its so important even just for life

I dont understand what to do after you mutiply

After you multiply the base and height of the triangle, you have a parallelogram that is twice the size of the triangle you started out with. To get the area of your triangle and not this parallelogram, you have to divide by 2. You might be interested in this Khan Academy video, which tells you why the formula for a triangle is the way it is - https://www.khanacademy.org/math/geometry-home/geometry-area-perimeter/geometry-area-triangle/v/triangle-area-proofs

Main content

Basic geometry and measurement

Course: Basic geometry and measurement > Unit 8

Lesson 2: Area of triangles

Area of triangles

CCSS.Math:

6.G.A.1

Google Classroom

Intuition for why the area of a triangle is one half of base times height.

Intuition for why the area of a triangle is A, equals, start fraction, 1, divided by, 2, end fraction, b, h

To see why the formula makes sense, drag the dot all the way to the right:

Whoa! You made a rectangle that's twice as big as the triangle! The area of the rectangle is b, h, equals, 4, times, 5, equals, 20 square units, so the area of the triangle is start fraction, 1, divided by, 2, end fraction, b, h, equals, start fraction, 1, divided by, 2, end fraction, times, 4, times, 5, equals, 10 square units.

Key intuition: A triangle is half as big as the rectangle that surrounds it, which is why the area of a triangle is one-half base times height.

Practice problem 1

What is the area of the triangle?
Drag the dot to help you remember the formula.

unitssquared

Practice problem 2: right triangle

What is the area of the triangle?
Drag the dot to help you remember the formula.

unitssquared

Practice problem 3: one vertex is hanging over the side

What is the area of the triangle?
Drag the dot to help you remember the formula.

unitssquared

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Stephanie Pearce
Posted 5 years ago. Direct link to Stephanie Pearce's post “Do we need math in our li...”
Do we need math in our life mostly people dont use it in the modern world only high tec jobs do
Button navigates to signup pageComment on Stephanie Pearce's post “Do we need math in our li...”
(150 votes)
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- Olivia Carpenter
  Posted 4 years ago. Direct link to Olivia Carpenter's post “math is the foundation of...”
  math is the foundation of everything. think about it you need to know how many dollar socks you can get, the amount of tip to leave, or even what your Christmas gifts will cost.
  Comment on Olivia Carpenter's post “math is the foundation of...”
  (92 votes)
maryannefalli
Posted 5 years ago. Direct link to maryannefalli's post “This is very helpful! Do...”
This is very helpful! Does this work for all triangles?
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(102 votes)
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- Klemmie
  Posted 6 months ago. Direct link to Klemmie's post “_Yes! it works for all tr...”
  Yes! it works for all triangles!
  Comment on Klemmie's post “_Yes! it works for all tr...”
  (25 votes)
LilD
Posted 5 years ago. Direct link to LilD's post “why do you want to find a...”
why do you want to find area of a triangle
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(33 votes)
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- Harry Mary :]
  Posted 4 months ago. Direct link to Harry Mary :]'s post “why...... why have a tria...”
  why...... why have a triangular room.....WHYYYYY
  Comment on Harry Mary :]'s post “why...... why have a tria...”
  (10 votes)
myaphill1
Posted 4 years ago. Direct link to myaphill1's post “do you have to divide it ...”
do you have to divide it by two
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(19 votes)
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- Allixxison AKA Imposter !
  Posted 3 years ago. Direct link to Allixxison AKA Imposter !'s post “if you dont you are techn...”
  if you dont you are technically doing normal rectangle area
  Comment on Allixxison AKA Imposter !'s post “if you dont you are techn...”
  (12 votes)
Shannon Ritchie
Posted 4 years ago. Direct link to Shannon Ritchie's post “the triangles are hard to...”
the triangles are hard to do sometimes.
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(16 votes)
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- heilbel
  Posted 6 months ago. Direct link to heilbel's post “yea but youjust have to d...”
  yea but youjust have to do it a ot
  Comment on heilbel's post “yea but youjust have to d...”
  (2 votes)
ayse.sahingoz
Posted 3 years ago. Direct link to ayse.sahingoz's post “i feel like monkeys can s...”
i feel like monkeys can solve this but not me XD jk
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palwasha.asif
Posted 5 years ago. Direct link to palwasha.asif's post “is there any other formul...”
is there any other formula which can be used to find an area of a triangle
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(14 votes)
Answer
- Elmion
  Posted 2 years ago. Direct link to Elmion's post “1) abc/4R (R is radius of...”
  1) abc/4R (R is radius of circumscribed circle)
  2) r/2×(a+b+c) (r is radius of inscribed circle)
  3) If you know the coordinates of the three points, use the shoelace formula
  1/2×|x₁y₂+x₂y₃+x₃y₁-x₂y₁-x₃y₂-x₁y₃|
  Comment on Elmion's post “1) abc/4R (R is radius of...”
  (5 votes)
Elijah Blackmon
Posted 3 years ago. Direct link to Elijah Blackmon's post “I will accept all the hel...”
I will accept all the help I can get because I can really make use of it.
Button navigates to signup pageButton navigates to signup page
(10 votes)
Answer
- Bradley Swalberg
  Posted 3 years ago. Direct link to Bradley Swalberg's post “Use the formula base (usu...”
  Use the formula base (usually the bottom part of the triangle) times the height (the distance from the very top point of the triangle down to the middle of the base) divided by 2. Usually the height is represented as a dotted line.
  Button navigates to signup page
  (8 votes)
Taylor :]
Posted 3 years ago. Direct link to Taylor :]'s post “I dont understand what to...”
I dont understand what to do after you mutiply
Button navigates to signup pageComment on Taylor :]'s post “I dont understand what to...”
(5 votes)
Answer
- Hecretary Bird
  Posted 3 years ago. Direct link to Hecretary Bird's post “After you multiply the ba...”
  After you multiply the base and height of the triangle, you have a parallelogram that is twice the size of the triangle you started out with. To get the area of your triangle and not this parallelogram, you have to divide by 2.
  You might be interested in this Khan Academy video, which tells you why the formula for a triangle is the way it is - https://www.khanacademy.org/math/geometry-home/geometry-area-perimeter/geometry-area-triangle/v/triangle-area-proofs
  Comment on Hecretary Bird's post “After you multiply the ba...”
  (11 votes)
lefago2532
Posted 8 months ago. Direct link to lefago2532's post “Is math really “that impo...”
Is math really “that important?” That’s why god invented calculators isn’t it.
Button navigates to signup pageComment on lefago2532's post “Is math really “that impo...”
(7 votes)
Answer
- jenifferlee01
  Posted 5 months ago. Direct link to jenifferlee01's post “yes cause without math mi...”
  yes cause without math millions of things wouldn't be invented just like khan academy. computers, phones, tablets, buildings, and even parks wouldnt be here if it weren't for math, that's why its so important even just for life
  Comment on jenifferlee01's post “yes cause without math mi...”
  (5 votes)

Basic geometry and measurement

Course: Basic geometry and measurement > Unit 8

Intuition for why the area of a triangle is A=12bhA=\dfrac{1}{2}bhA=21​bhA, equals, start fraction, 1, divided by, 2, end fraction, b, h

Practice problem 1

Practice problem 2: right triangle

Practice problem 3: one vertex is hanging over the side

Want to join the conversation?

Intuition for why the area of a triangle is A, equals, start fraction, 1, divided by, 2, end fraction, b, h