Class 10 Maths Triangles | Similarity of Triangles |

**Similarity of Triangles**

Two triangles are similar, if

- their corresponding angles are equal
**Or** - Their corresponding sides are in the same ratio (or proportion).

Both mean same things. If one is true, other has to be true.

If corresponding angles of two triangles are equal, then they are known as equiangular triangles.

**Thales theorem:** The ratio of any two corresponding sides in two equiangular triangles is always the same.

**Theorem 1 : **If a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, the other two sides are divided in the same ratio.

Refer ExamFear video lesson for Proof for this theorem.

**Converse Theorem 2**: If a line divides any two sides of a triangle in the same ratio, then the line is parallel to the third side

Refer ExamFear video lesson for Proof for this theorem.

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