Q19. State and prove Angle sum property of a triangle. Using this result, find the value of p and all the
Answers
Answered by
0
Step-by-step explanation:
To prove the above property of triangles, draw a line \overleftrightarrow {PQ} parallel to the side BC of the given triangle. Thus, the sum of the interior angles of a triangle is 180°.
Answered by
0
Answer:
Theorem 1:
Prove that sum of all three angles is 180° or 2 right angles.
Given: ∆ABC
To prove: ∠A + ∠B + ∠C = 180°
Construction: Draw PQ || BC, passes through point A.
Angle-Sum-Property-of-a-Triangle-theorem-1
Proof: ∠1 = ∠B and ∠3 = ∠C ……. (i)
[∵ alternate angles ∵ PQ || BC]
∵ PAQ is a line
∴∠1 + ∠2 + ∠3 = 180° (linear pair application)
∠B + ∠2 + ∠C = 180°
∠B + ∠CAB + ∠C = 180°
= 2 right angles.
Proved.
Read More:
Similar questions