Practice MCQ Questions and Answer on Triangles

11.

In ΔABC, two points D and E are taken on the lines AB and BC respectively in such a way that AC is parallel to DE. Then ΔABC and ΔDBE are :

  • (A) Similar only if D lies outside the line segment AB
  • (B) Congruent only If D lies out side the line segment AB
  • (C) Always similar
  • (D) Always congruent

12.

The sum of three altitudes of a triangle is

  • (A) Equal to the sum of three sides
  • (B) Less than the sum of sides
  • (C) Greater than the sum of sides
  • (D) Twice the sum of sides

13.

If the sides of a right angled triangle are three consecutive integers, then the length of the smallest side is

  • (A) 3 units
  • (B) 2 units
  • (C) 4 units
  • (D) 5 units

14.

ABC is a right-angled triangle with AB = 6 cm and BC = 8 cm. A circle with center O has been inscribed inside ΔABC. The radius of the circle is

  • (A) 1 cm
  • (B) 2 cm
  • (C) 3 cm
  • (D) 4 cm

15.

If the median drawn on the base of a triangle is half of its base the triangle will be

  • (A) Right-angled
  • (B) Acute-angled
  • (C) Obtuse-angled
  • (D) Equilateral

16.

In ΔABC, AC = BC and âˆÂ ABC = 50°, the side BC is produced to D so that BC = CD then the value of âˆÂ BAD is:

  • (A) 80°
  • (B) 40°
  • (C) 90°
  • (D) 50°

17.

In a ΔABC, AB = AC and BA is produced to D such that AC = AD. Then the âˆÂ BCD is :

  • (A) 100°
  • (B) 60°
  • (C) 80°
  • (D) 90°

18.

Given that the ratio of altitudes of two triangles is 4 : 5, ratio of their areas is 3 : 2, the ratio of their corresponding bases is :

  • (A) 5 : 8
  • (B) 15 : 8
  • (C) 8 : 5
  • (D) 8 : 15

19.

In ΔABC, AD âŠÂ¥ BC, then

  • (A) AB2 - BD2 = AC2 - CD2
  • (B) AB2 + BD2 = AC2 - CD2
  • (C) AB2 - BD2 = AC2 + CD2
  • (D) AB2 - AC2 = BD2 + CD2

20.

If ABC is an equilateral triangle and D is a point of BC such that AD âŠÂ¥ BC, then

  • (A) AB : BD = 1 : 1
  • (B) AB : BD = 1 : 2
  • (C) AB : BD = 2 : 1
  • (D) AB : BD = 3 : 2