WebArea of Equilateral Triangle $= \frac{\sqrt{3}a^2}{4} square units. Using Heron’s Formula. When the lengths of the three sides of the triangle are known, Heron’s formula is used to … WebABC is a triangle in which ∠A= 72∘, the internal bisectors of angles B and C meet in O. Find the magnitude of ∠BOC. Solution In ΔABC,∠A= 72∘ and bisectors of ∠B and ∠ C meet at O. Now ∠B+∠C = 180∘−72∘ =108∘ ∵ OB and OC are the bisectors of ∠B and ∠C respectively ∴ ∠OBC+∠OCB= 1 2(∠B+∠C) = 1 2×108∘ =54∘ But in ΔOBC, ∴ ∠OBC+∠OCB+∠BOC= 180∘

In triangle ABC, AD is the internal bisector of angle A. If BD = 5 cm ...

WebApr 11, 2024 · Hint: Use the Angle Bisector theorem, An angle bisector of a triangle will divide the opposite side into two segments that are proportional to the other two sides of triangle. Here: \[\dfrac{BD}{DC}=\dfrac{AB}{AC}\] Angle bisector is a line which bisects the internal angle exactly by half. So from above figure we can say WebWe know that BD is the angle bisector of angle ABC which means angle ABD = angle CBD. Now, CF is parallel to AB and the transversal is BF. So we get angle ABF = angle BFC ( … ea babies\u0027-breath

[Solved] In triangle ABC, the bisector of the internal ∠B an - Testbook

WebWe know that BD is the angle bisector of angle ABC which means angle ABD = angle CBD. Now, CF is parallel to AB and the transversal is BF. So we get angle ABF = angle BFC ( alternate interior angles are equal). But we already know angle ABD i.e. same as angle ABF = angle CBD which means angle BFC = angle CBD. WebGiven: ∆ABC is an isosceles triangle in which AB = AC. Side BA is produced to D such that AD = AB. To Prove: ∠BCD is a right angle. Proof: ∵ ABC is an isosceles triangle ∴ ∠ABC = ∠ACB ...(1) ∵ AB = AC and AD = AB ∴ AC = AD. ∴ In ∆ACD, ∠CDA = ∠ACD Angles opposite to equal sides of a triangle are equal cs go monitor response time