Question

prove that the sum of angles of a triangle is 180 degrees
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Answer 1

Answer:

Given :

• A  triangle   ⧍ABC.

To prove :

• ∠A+∠B+∠C=180°  ⟹ ∠1+∠2+∠3=180 °

Construction :

• Through A, draw a line l parallel to BC.

Proof :

• Since l∥BC. Therefore,
• ∠2 = ∠4 .......eq(i)
• ∠3=∠5......eq(ii)

adding  eq(i)and(ii)

Therefore, ∠2+∠3=∠4+∠5

∠1+∠2+∠3=∠1+∠4+∠5  [adding ∠1 both Side]

∠1+∠2+∠3=180  

Thus, the sum of three angles of a triangle is 180  .

• In order to prove that the sum of angles of a triangle is 180, you must know the theorems of angles of a triangle. We know that, alternate interior angles are of equal magnitude. ... Now we have to substitute the angles. ∠PAB + ∠BAC + ∠CAQ = 180°

___________________

             ⧍

• Name : Triangle

• Sides : 3

• Interior angle : 180°

• It is a polygon

• There are three types of triangle

Step-by-step explanation: