LINES AND ANGLES NCERT 9 MATHEMATICS TEXTBOOK MCQ (Multiple Choice Questions)

Q1. Given ∠ POR = 3x and ∠ QOR = 2x + 10. If POQ is a straight line, then the value of x is

  1. 30˚
  2. 34˚
  3. 36˚
  4. None of these

Q2. If two parallel lines are intersected by a transversal, then the bisectors of any two corresponding angles are

  1. parallel
  2. perpendicular
  3. Intersect
  4. bisect each other

Q3. Find the measure of the angle which is complement of itself.

  1. 30o
  2. 90O
  3. 45O
  4. 180o

Q4. If the measures of angles of a triangle are in the ratio 3:4:5. What is the measure of the smallest angle of the triangle?

  1. 25˚
  2. 30˚
  3. 45˚
  4. 60˚

Q5. If two parallel lines are intersected by a transversal, then interior angles on the same side of the transversal are

  1. Linear pair
  2. Complementary
  3. Supplementary
  4. Equal

Q6. If one angle of a triangle is equal to the sum of the other two angles, then the triangle is:

  1. An isosceles triangle
  2. An obtuse angled triangle
  3. An equilateral triangle
  4. A right triangle

Q7. Two supplementary angles are in the ratio 4:5. The angles are :

  1. 90o, 90o
  2. 80o, 100o
  3. 30o, 150o
  4. 45o,45o

Q8. Measure of an angle which is supplement of itself is :

  1. 45o
  2. 30o
  3. 90o
  4. 180o

Q9. An exterior angle of triangle is 80o and the interior opposite angles are in the ratio 1:3. Measure of each interior opposite angle is:

  1. 30o, 90o
  2. 40o, 120o
  3. 20o, 60o
  4. 30o, 60o

Q10. Of the three angles of a triangle, one is twice the smallest and another is thrice the smallest. The angles of the triangle will be

  1. 40o, 60o, 80o
  2. 70o, 50o, 60o
  3. 60o, 90o, 30o
  4. 80o, 50o, 50o

Q11. Two complementary angles are such that two times the measure of one is equal to three times the measure of the other. The measure of the smaller angle is

  1. 45˚
  2. 30˚
  3. 36˚
  4. 20˚

Q12. If a side of a triangle is produced, the exterior angle so formed is equal to the

  1. Sum of adjacent angles of the triangle
  2. Sum of interior opposite angles of the triangle
  3. Sum of exterior angles
  4. Sum of exterior opposite angles

Q13. If two straight lines are perpendicular to a line l, then they are.

  1. Perpendicular to each other
  2. Parallel to each other
  3. The angle between the two lines is 180o
  4. The lines intersect each other when extended

Q14. The angles of a triangle are in the ratio 2: 3: 4; the three angles are

  1. 40o, 60o, 80o
  2. 70o, 46o, 64o
  3. 60o, 90o, 30o
  4. 80o, 50o, 50o

Q15. An exterior angle of a triangle is 80o and two interior opposite angles are equal. Measure of each of these angle is:

  1. 120o
  2. 40o
  3. 100o
  4. 60o

Q16. The angle whose complement is one-third of its supplement will be

  1. 90o
  2. 135o
  3. 180o
  4. 45o

Q17. If the bisectors of the acute angles of a right triangle meet at O, then the angle at O between the two bisectors is

  1. 45˚
  2. 95˚
  3. 135˚
  4. 90˚

Q18. If a side of a triangle is produced, then the exterior angle so formed is equal to the sum of the ____ interior opposite angles.

  1. Two
  2. Three
  3. One
  4. Four

Q19. Two lines are parallel to each other, only when

  1. The lines lie on the same plane
  2. They do not intersect each other when extended on either side
  3. They are parallel to the plane in which they lie
  4. Their point of intersection is at infinity

Q20. Given four points such that no three of them are collinear, then the number of lines that can be drawn through them are:

  1. 2 lines
  2. 4 lines
  3. 6 lines
  4. 8 lines

Q21. If the angles of a triangle are 2x, 5x and 3x, then find the accurate value of angles.

  1. 45°, 90° and 45°
  2. 26°, 90° and 64°
  3. 55°, 90° and 35°
  4. 36°, 90° and 54°

Q22. If two straight lines are perpendicular to a line l, then they are

  1. Perpendicular to each other
  2. Parallel to each other
  3. The angle between the two lines is 180o
  4. The lines intersect each other when extended

Q23. Choose the correct statement out of the following.

  1. If two adjacent angles are equal, then each angle measures 90o
  2. Angles forming a linear pair can both be acute angles
  3. If angles forming a linear pair are equal, then each of these angles measures 90o
  4. Two angles whose sum is 90o are called supplementary angles

Q24. Two lines are parallel to each other, only when

  1. The lines lie on the same plane
  2. They do not intersect each other when extended on either side
  3. They are parallel to the plane in which they lie
  4. Their point of intersection is a unique point

Q25. If two parallel lines are intersected by a transversal then, pair of alternate interior angles are:

  1. Equal
  2. Complementary
  3. Supplementary
  4. Sum of the two angles is 360o

Q26. The angles of a triangle are in the ratio 2 : 3 : 4. The angles, in order, are :

  1. 20o, 60o, 80o
  2. 80o, 40o, 60o
  3. 40o, 60o, 80o
  4. 60o, 40o, 80o

Q27. The sum of two angles of a triangle is 116o and their difference is 24o. The measure of each angle of the triangle is

  1. 40o, 60o, 80o
  2. 60o, 90o, 30o
  3. 70o, 50o, 60o
  4. 70o, 46o, 64o

Q28. One of the angles of a triangle is 75o. If the difference of the other two angles is 35o, then the larger angle of the other two angles of the triangle has a measure of:

  1. 80o
  2. 70o
  3. 100o
  4. 135o

Q29. If two lines intersect each other, then the vertically opposite angles are ……….

  1. Equal
  2. Unequal
  3. Complementary
  4. Supplementary

Q30. A pair of angles is called linear pair if sum of two adjacent angles is:

  1. 90o
  2. 180o
  3. 270o
  4. 360o

Q31. Sum of the measure of an angle and its vertically opposite angle is always.

  1. Double the measure of the original angle
  2. Thrice the measure of the original angle
  3. Equal to the measure of the original angle
  4. Zero

Q32. An exterior angle of a triangle is 110o; and one of the interior opposite angles is 30o, then the other two angles of the triangle are

  1. 60o, 70o
  2. 120o, 80o
  3. 70o,  80o
  4. 50o,   60o

Q33. Two parallel lines l and m are such that A, C are the points on l and B, D are the points on m.  AB and CD are perpendicular to both l and m. If AB = 4 cm, then CD =

  1. 2 cm
  2. 8 cm
  3. 4 cm
  4. 1 cm

Q34. If the measure of an angle is twice the measure of its supplementary angle then the measure of the angle is:

  1. 60°
  2. 90°
  3. 120°
  4. 130°

Q35. If a transversal intersects two parallel lines, then the consecutive interior angles are

  1. complementary
  2. equal
  3. supplementary
  4. congruent

Q36. If in triangle DEF, the greatest angle is twice the smallest and the third angle is 20 degrees more than the smallest, what are the angles?

  1. 30o, 60o, 80o
  2. 20o, 40o, 40o
  3. 40o, 60o, 80o
  4. 30o, 50o, 100o

Q37. If two interior angles on the same side of a traversal intersecting two parallel lines are in the ratio 2: 3, then the smaller of the two angles is:

  1. 72o
  2. 108o
  3. 54o
  4. 36o

Q38. If a transversal intersects two parallel lines, then each pair of corresponding angles is ………

  1. Parallel
  2. Perpendicular
  3. Equal
  4. Different

Q39. Choose the correct statement

  1. If two adjacent angles are equal, then each angle measures 90o.
  2. Angles forming a linear pair can both be acute angles.
  3. If angles forming a linear pair are equal, then each of these angles measures 90o.
  4. Two angles whose sum is 90o are called supplementary angles.

Q40. The number of lines that can pass through a given point is:

  1. Two
  2. None
  3. Only one
  4. Infinitely many