Question

if the side of a triangle is extended, the exterior angles so formed is equal to the sum of the interior opposite angles.

Prove this exterior angle theorem..............
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Answer 1

Answer:

Step-by-step explanation:

IN TRAINGLE ABC

∠2 + ∠3 + ∠4 = 180  ---------(I)

(ANGLE SUM PROPERTY OF TRIANGLE)

ALSO

∠2 + ∠1 = 180 (LINEAR PAIR AXIOM) ---------------(II)

FROM (I) & (II)

∠2 + ∠1 = ∠2 + ∠3 + ∠4

SO

⇒ ∠1 = ∠3 + ∠4

HENCE PROVED