GEOMETRY
Similar triangles
Geometrical
figures which have same shape but proportional sizes. These figures are called
“similar”.
Angle Bisector Theorem
Statement
The internal bisector of an angle
of a triangle divides the opposite side internally in the ratio of the
corresponding sides containing the angle.
Given
In DABC, AD is the internal
bisector
To Prove
|
No |
Statement |
Reason |
|
1. |
∠AEC= ∠BAE= |
Two parallel lines cut by a transversal make
alternate angles equal |
|
2. |
∆ACE is isosceles AC = CE … (1) |
In ∆AEC, ∠CAE =∠CEA |
|
3. |
∆ABD ̴∆ECD |
By AA Similarity |
|
4. |
|
From (1) AC CE. Hence proved |
Construction of triangle
Construction of tangents to a circle
Construction of a tangent to a circle
Constructing of a tangent
to a circle using center and radius is given. Steps involved
Special cevians