NCERT Solutions For Class 10 Maths Chapter 6 Triangles Ex 6.5

Ex 6.5 Class 10 Maths Question 1.

Sides of triangles are given below. Determine which of them are right triangles. In case of a right triangle, write the length of its hypotenuse.
(i) 7 cm, 24 cm, 25 cm
(ii) 3 cm, 8 cm, 6 cm
(iii) 50 cm, 80 cm, 100 cm
(iv) 13 cm, 12 cm, 5 cm

Solution for Ex 6.5 Class 10 Maths Question 1 Ex 6.5 Class 10 Maths Question 2.

PQR is a triangle right angled at P and M is a point on QR such that PM ⊥ QR. Show that PM2 = QM X MR.

Solution for Ex 6.5 Class 10 Maths Question 2 Ex 6.5 Class 10 Maths Question 3.

In the given figure, ABD is a triangle right angled at A and AC i. BD. Show that
(i) AB2 = BC.BD
(ii) AC2 = BC.DC Solution for Ex 6.5 Class 10 Maths Question 3 Ex 6.5 Class 10 Maths Question 4.

ABC is an isosceles triangle right angled at C. Prove that AB2 = 2AC2.

Solution for Ex 6.5 Class 10 Maths Question 4 Ex 6.5 Class 10 Maths Question 5.

ABC is an isosceles triangle with AC = BC. If AB2 = 2AC2 , Prove that ABC is a right triangle.

Solution for Ex 6.5 Class 10 Maths Question 5 Ex 6.5 Class 10 Maths Question 6.

ABC is an equilateral triangle of side la. Find each of its altitudes.

Solution for Ex 6.5 Class 10 Maths Question 6 Ex 6.5 Class 10 Maths Question 7.

Prove that the sum of the squares of the sides of a rhombus is equal to the sum of the squares of its diagonals.

Solution for Ex 6.5 Class 10 Maths Question 7 Ex 6.5 Class 10 Maths Question 8.

In the given figure, O is a point in the interior of a triangle ABC, OD ⊥ BC, OE ⊥ AC and OF ⊥ AB. Show that
(i) OA2 + OB2 + OC2 – OD2 – OE2 – OF2 = AF2 + BD2 + CE2
(ii) AF2 + BD2 + CE2 = AE2 + CD2 + BF2. Solution for Ex 6.5 Class 10 Maths Question 8 Ex 6.5 Class 10 Maths Question 9.

A ladder 10 m long reaches a window 8 m above the ground. ind the distance of the foot of the ladder from base of the wall.

Solution for Ex 6.5 Class 10 Maths Question 9 Ex 6.5 Class 10 Maths Question 10.

A guy wire attached to a vertical pole of height 18 m is 24 m long and has a stake attached to the other end. How far from the base of the pole should the stake be driven so that the wire will be taut?

Solution for Ex 6.5 Class 10 Maths Question 10 Ex 6.5 Class 10 Maths Question 11.

An aeroplane leaves an airport and flies due north at a speed of 1000 km per hour. At the same time, another aeroplane leaves the same airport and flies due west at a speed of 1200 km per hour. How far apart will be the two planes after hours?

Solution for Ex 6.5 Class 10 Maths Question 11 Ex 6.5 Class 10 Maths Question 12.

Two poles of heights 6 m and 11m stand on a plane ground. If the distance between the feet of the poles is 12 m, find the distance between their tops.

Solution for Ex 6.5 Class 10 Maths Question 12 Ex 6.5 Class 10 Maths Question 13.

D and E are points on the sides CA and CB respectively of a triangle ABC right angled at C. Prove that AE2 + BD2 = AB2 + DE2.

Solution for Ex 6.5 Class 10 Maths Question 13 Ex 6.5 Class 10 Maths Question 14.

The perpendicular from A on side BC of a ∆ABC intersects BC at D such that DB = 3CD (see the figure). Prove that 2AB= 2AC2 + BC2. Solution for Ex 6.5 Class 10 Maths Question 14 Ex 6.5 Class 10 Maths Question 15.

In an equilateral triangle ABC, D is a point on side BC, such that BD = BC. Prove that 9AD2 = 7AB2.

Solution for Ex 6.5 Class 10 Maths Question 15 Ex 6.5 Class 10 Maths Question 16.

In an equilateral triangle, prove that three times the square of one side is equal to four times the square of one of its altitudes.

Solution for Ex 6.5 Class 10 Maths Question 16 Ex 6.5 Class 10 Maths Question 17.

Tick the correct answer and justify : In ∆ABC, AB = 12 cm and BC = 6 cm. The angle B is:
(a) 120°
(b) 60°
(c) 90°
(d) 45

Solution for Ex 6.5 Class 10 Maths Question 17 