In this article provides the simple tricks with formulas to find the number of triangles for the following figures

- Counting triangles with in Square, Rectangle, Quadrilateral
- Number of possible triangles within a triangle

## How to Calculate Number of Triangles in a Square | Trick to Count no of Triangles

**Calculate number of triangles in a square**

**Type – 1 : Counting triangles with in Square, Rectangle, Quadrilateral **

* Figure – 1 :* Number of triangles in Fig – 1 = 8

**Hint:** Here having total two diagonals and having four blocks. So formula for that 4 x 2 = 8 number of triangles.

* Figure – 2 :* Number of triangles in Fig – 2 = 16

**Hint:** Here having total two diagonals and having eight blocks. So formula for that 8 x 2 = 16 number of triangles.

** Figure – 3 **: Number of triangles in Fig – 3 = 18

**Hint:** Here each square having 8 no. of triangles and combine squares having 2 no. of triangles. So total number of triangles – 8 + 8 + 2 = 18.

** Figure – 4 : **Number of triangles in Fig – 3 = 28

**Hint:** Here each square having 8 no. of triangles and combine squares having 4 no. of triangles. So total number of triangles – 8 + 8 + 8 + 4 = 28.

**Type – 2 : Counting triangles with the ****Triangle having number of bisects with vertex
**

**Count the number of possible triangles in the above figures**

*Figure – 5:* Number of possible triangles in Fig – 5 = 1

*Figure – 6 :* Number of possible triangles in Fig – 6 = 3

**Formula :** Here number of parts ” n” then possible triangles is n (n+1) /2

*Figure – 7 :* Number of possible triangles in Fig – 7 = 10

**Hint :** No of parts ” n” = 4 so according to formula 4 x 5 /2 = 10

*Figure – 8 :* Number of possible triangles in Fig – 8 = 15

**Hint :** No of parts ” n” = 5 so according to formula 5 x 6 /2 = 15.