Question

Write angle sum property for triangles.


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Answer 1

Step-by-step explanation:

• In geometry, the interior angles of a triangle are the angles that are formed inside a triangle. Interior angles have the following properties: The sum of interior angles is 180 degrees (Triangle Angle Sum Theorem). All interior angles of a triangle are more than 0° but less than 180°.

Answer 2

Answer:

The sum of the interior angles of a triangle is 180⁰

Step-by-step explanation:

It could be proved by

$\red{ \bold{to \: prove}} \\ \angle1 + \angle2 + \angle3 = 180 \degree$

Construction:

Draw DE || BC through A

$\angle4 = \angle2 \\ \angle5 = \angle3$

(angle 4,2 and angle 5,3 are alternate interior angles)

$\implies \: \angle1 + \angle2 + \angle3 = \angle4 + \angle5 + \angle6$

$\angle4 + \angle5 + \angle6 = 180 \degree$

(Because angles 4,5 and 6 are on a straight line)

$\tt{\bold{ \red{hence \: proved}}}$