Question

What is exterior angle property

Answer 1

exterior angles equal to sum of opposite angles

Answer 2

Exterior angle property

Exterior and interior opposite angle

In a triangle is a side of a triangle is produced in

either direction the angles so formed with any of

the other side is called the exterior angle of the

triangle. The angle inside the triangle opposite of

the exterior angles so formed are called the

interior opposite angle.

Verification of exterior angle property by paper cutting and pasting.

•In note draw a triangle and produce one of its

sides to form an exterior angle trace this figure

on to your craft sheet.

•Mark interior angles on your craft seat.

•In the given figure∆ACD is the exterior angle;<A

and<B are interior opposite angle.

•Cut out<A and <B from the craft sheet accurately

along the arms.

•Best this as adjacent angle carefully matching

the arms on<AXD in your notebook.

Thus, we can see that <ACD=<A+<B

Thus, we can see that <ACD=<A+<BThis verify that the exterior angle of the triangle

Thus, we can see that <ACD=<A+<BThis verify that the exterior angle of the triangle is equal to the sum of the interior positive angle.

Proof of exterior angle property.

In ∆PQR,side PR is produced to S, forming an

exterior angle QRS.<1 and <3 are interior positive angle.

<1+<2+<3=180°(angle sum property)

<4+<2=189°(Linear pair)

So,

<1+<2+<3=<4+<2. [By using (1) and (2)]

therefore

<1+<3=<4+<2

or

<4=<1+<3

Thus,the exterior angle is equal to the sum of the interior opposite angle.