This is a new educational channel called Smart Friday!
Every Friday we will share with you an informational piece about a topic we care about! You can use it in your classroom, share it, learn and enjoy it!.
Today, we are going to learn about the Triangle Inequality Theorem. Let's get started!
In Mathematics, the triangle inequality states that for any triangle, the sum of the lengths of any two sides must be greater than the length of the remaining side.
| A + B > C |
| B + C > A |
| A + C > B |
* Remember that this rule must be satisfied for all 3 conditions of the sides.
| 10 + 3 > 4 |  |
| 10 + 4 > 3 | |
| 4 + 3 > 10 |  |
*As soon as 1 pair do not sum up to a greater lenght than the third, you know that the 3 sides cannot make a triangle
Let's see how much you have learned!
Answer the following problems applying the Triangle Inequality Theorem!
Problem 1
If A=7 and C=8 what would be the value of B to complete the theorem?
a: 15
b: 8
c: 20
Answer
If you chose B Congratulations! that is the right answer because if you sum 8+8 =16 and that is higher than 7 and higher than 15. Remember that the theorem says that the sum of two sides can't be less or equal to the third side that's why A and C are not correct!
Problem 2
If B= 5 and C= 15 the sum of these two sides is 20 what is the number that represents A to solving the theorem?
a: 5
b: 15
c: 20
Answer
If you chose B Congratulations! that is the right answer because applying the theorem the sum of 15+15 is equal to 30 beign higher than 5. Remember that the theorem says that the sum of two sides can't be less or equal to the third side that's why A and C are not correct!
Let's play a zombie game applying today's Lessons
A zombie is chasing you on the roof of the flatiron building and there’s an escape to take some secret stairs , which is the quickest way to get there
a: Side C
b: Side B
c: I can't escape
Answer B : Side B
Do you want to learn more?
If you like this lesson about triangles and you want to learn more in a fun and engaging way go to our Learning Platform Engage!K12 and browse hundreds of lessons for you! 
