Chapter 7 – Triangles

2. In ΔABC, AD is the perpendicular bisector of BC (see Fig. 7.30). Show that ΔABC is an isosceles triangle in which AB = AC. 2. In ΔABC AD is the perpendicular bisector of BC (see Fig. 7.30). Show that ΔABC is an isosceles triangle in which AB = AC. October 15, 2020 Category: Chapter [...]

1. In an isosceles triangle ABC, with AB = AC, the bisectors of angle B and angle C intersect each other at O. Join A to O. Show that: (i) OB = OC (ii) AO bisects angle A 1. In an isosceles triangle ABC the bisectors of angle B and angle C intersect each other [...]

8. In right triangle ABC, right angled at C, M is the mid-point of hypotenuse AB. C is joined to M and produced to a point D such that DM = CM. Point D is joined to point B (see figure). Show that (i) ∆AMC ≅ ∆BMD (ii) ∠DBC is a right angle (iii) ∆DBC [...]

7. AB is a line segment and P is its mid-point. D and E are points on the same side of AB such that ∠ BAD = ∠ ABE and ∠ EPA = ∠ DPB. (see figure). Show that (i) ∆DAP ≅ ∆EBP (ii) AD = BE 7. AB is a line segment and P [...]

6.In figure, AC = AE, AB = AD and ∠BAD = ∠EAC. Show that BC = DE. 6.In figure AB = AD and ∠BAD = ∠EAC. Show that BC = DE. AC = AE October 15, 2020 Category: Chapter 7 - Triangles , Maths , NCERT Class 9 ,

5. Line l is the bisector of an ∠ A and ∠ B is any point on l. BP and BQ are perpendiculars from B to the arms of angle A (see figure). Show that (i) ∆APB ≅ ∆AQB (ii) BP = BQ or B is equidistant from the arms ot ∠A. AC = AD [...]

4. l and m are two parallel lines intersected by another pair of parallel lines p and q (see figure). Show that ∆ABC = ∆CDA. 4. l and m are two parallel lines intersected by another pair of parallel lines p and q (see figure). Show that ∆ABC = ∆CDA. October 15, 2020 Category: Chapter [...]

3. AD and BC are equal perpendiculars to a line segment AB (see figure). Show that CD bisects AB. 3. AD and BC are equal perpendiculars to a line segment AB (see figure). Show that CD bisects AB. October 15, 2020 Category: Chapter 7 - Triangles , Maths , NCERT Class 9 ,

2. ABCD is a quadrilateral in which AD = BC and ∠ DAB = ∠ CBA (see figure). Prove that (i) ∆ABD ≅ ∆BAC (ii) BD = AC (iii) ∠ABD = ∠ BAC 2. ABCD is a quadrilateral in which AD = BC and ∠ DAB = ∠ CBA (see figure). Prove that (i) ∆ABD [...]

In quadrilateral ACBD, AC = AD and AB bisects ∠ A (see figure). Show that ∆ABC ≅ ∆ABD. What can you say about BC and BD? AC = AD and AB bisects ∠ A (see figure). Show that ∆ABC ≅ ∆ABD. What can you say about BC and BD? In quadrilateral ACBD October 15, 2020 [...]