1 decade ago. To prove: ∠BCD = 90° 10:00 AM to 7:00 PM IST all days. ABC is an isosceles triangle with AB = AC and BD and CE are its two medians. Show that the ΔABC is an isosceles triangle if the determinant ← Prev Question Next Question → 0 votes . Solution: Example 2: In isosceles triangle DEF, DE = EF and ∠E = 70° then find other two angles. Learn Science with Notes and NCERT Solutions. some equilateral triangles are not isosceles. we need to find out if any two of the sides are of the same length and if any two of the internal angles are equal( remember not three angles- that will make it an equilateral triangle). AB = BC = AC To prove: A = B = C = 60 Proof: AB = AC C = B Also, AC = BC B = A From (1) & (2) A = B = C In ABC, A + B + C = 180 A + A + A = 180 3 A = 180 A A A = B = C = 60 Hence proved ∠ADC = ∠ACD In ΔACD, In a triangle ABC, AB = AC, D and E are points on the sides AB and AC respectively such that BD = CE. How to solve: Prove that in an isosceles triangle ABC, in which AB = AC and AD is the altitude, AD is also: i. median. 9,174 1 1 gold badge 4 4 silver badges 19 19 bronze badges \$\endgroup\$ \$\begingroup\$ Thanks, I misunderstood. R.H.S Show that A ABC is an isosceles triangle in which AB = AC. So, the perimeter is . 7.15). So \$\triangle ADC\$ is isosceles. We need to prove that the angles corresponding to the sides AC and BC are equal, that is, ∠CAB = ∠CBA. isosceles triangle means that 2 of the sides of the triangle are equal to each other. 140° Draw AP ⊥ BC to show that ∠ = ∠. Given Subscribe to our Youtube Channel - https://you.tube/teachoo, Ex 7.2, 6 9,174 1 1 gold badge 4 4 silver badges 19 19 bronze badges \$\endgroup\$ \$\begingroup\$ Thanks, I misunderstood. Proof: asked Mar 24, 2018 in Class XII Maths by rahul152 (-2,838 points) Show that the ABC is an isosceles triangle … This video is unavailable. asked Sep 20, 2018 in Class IX Maths by aditya23 ( -2,145 points) Teachoo provides the best content available! Triangle BCD is isosceles because 2 of the sides have equal side length (ie are congruent) Practice Problem 2) Triangle ABC has coordinate A (-2,3) , B (-5,-4) and C (2,-1) Using coordinate geometry, prove that triangle BCD is an isosceles triangle. Does it … Ex7.2, 8 Show that the angles of an equilateral triangle are 60 each. Watch Queue Queue Question Bank Solutions 7867. L.H.S Show that ∠BCD is a right angle. Ad is an altitude of an isosceles triangle ABC in which AB=AC.Show that AD bisects BC. 70° 3. Question 3: ABC is an isosceles triangle in which altitudes BE and CF are drawn to equal sides AC and AB respectively (see the given figure). where, AC = BC & AB2 = 2 AC2 To prove: ABC is a right angle triangle . If triangle ABC is an isosceles right triangle then one of the angles will be 90°. GJ bisects