Let’s take a look at some of the interesting questions from ‘A Tale of Three Intersecting Lines’ for Class 7 Maths, Chapter 7. In this chapter, you’ll explore triangles, their angle properties, and side relationships. To revise, you are going to attempt multiple-choice questions that test your ability to apply rules and solve tricky geometry problems. You will also be able to solve fill-in-the-blank questions to sharpen your memory of definitions, theorems, and key results.

Class 7 Maths Chapter 7 MCQ A Tale of Three Intersecting Lines
Question 1: A triangle with all three sides equal is called a ___.
a) Isosceles
b) Scalene
c) Equilateral
d) Right-angled
Answer:
c) Equilateral
Question 2: How many distinct altitudes can be drawn in any triangle?
a) 1
b) 2
c) 3
d) 4
Answer:
c) 3
Question 3: If two sides of a triangle are 7 cm and 9 cm, the third side must be less than ___.
a) 7 cm
b) 9 cm
c) 16 cm
d) 18 cm
Answer:
c) 16 cm
Question 4: Which of the following sets of lengths cannot form a triangle?
a) 6 cm, 8 cm, 10 cm
b) 3 cm, 4 cm, 8 cm
c) 5 cm, 5 cm, 7 cm
d) 7 cm, 9 cm, 15 cm
Answer:
b) 3 cm, 4 cm, 8 cm
Question 5: The sum of all three interior angles of a triangle is always ___.
a) 90°
b) 120°
c) 150°
d) 180°
Answer:
d) 180°
Question 6: If two angles of a triangle are 50° and 60°, the third angle is ___.
a) 50°
b) 60°
c) 70°
d) 80°
Answer:
c) 70°
Question 7: The exterior angle of a triangle is always equal to the sum of ___.
a) All three angles
b) Two adjacent angles
c) Two opposite interior angles
d) The largest angle only
Answer:
c) Two opposite interior angles
Question 8: A triangle with all three sides of different lengths is called ___.
a) Scalene
b) Isosceles
c) Equilateral
d) Right-angled
Answer:
a) Scalene
Question 9: Which of the following triangles can exist?
a) Sides 10 cm, 15 cm, 30 cm
b) Sides 2 cm, 3 cm, 6 cm
c) Sides 5 cm, 6 cm, 7 cm
d) Sides 1 cm, 1 cm, 5 cm
Answer:
c) Sides 5 cm, 6 cm, 7 cm
Question 10: If ∠A = 40° and ∠B = 75°, then ∠C = ___.
a) 55°
b) 65°
c) 75°
d) 85°
Answer:
a) 65°
Question 11: An isosceles triangle has two sides equal. If each equal side is 6 cm and the base is 8 cm, the triangle is ___.
a) Possible
b) Impossible
c) Equilateral
d) Right-angled
Answer:
a) Possible
Question 12: A right-angled triangle has one angle equal to 90°. The sum of the other two angles is ___.
a) 45°
b) 60°
c) 90°
d) 120°
Answer:
c) 90°
Question 13: Which of the following is true for any triangle?
a) Each angle = 90°
b) Sum of any two sides > third side
c) All three sides equal
d) One angle must be obtuse
Answer:
b) Sum of any two sides > third side
Question 14: If ∠A = 50° and ∠B = 60°, then the exterior angle at C is ___.
a) 50°
b) 60°
c) 110°
d) 120°
Answer:
c) 110°
Question 15: A triangle with all angles less than 90° is called ___.
a) Right-angled
b) Obtuse-angled
c) Acute-angled
d) Equilateral
Answer:
c) Acute-angled
Question 16: A triangle with one angle more than 90° is called ___.
a) Equilateral
b) Acute-angled
c) Right-angled
d) Obtuse-angled
Answer:
d) Obtuse-angled
Question 17: Which of the following angle sets cannot form a triangle?
a) 40°, 60°, 80°
b) 90°, 30°, 60°
c) 70°, 70°, 40°
d) 120°, 70°, 10°
Answer:
d) 120°, 70°, 10°
Question 18: In a triangle, if ∠A = ∠B and ∠C = 50°, then ∠A = ∠B = ___.
a) 50°
b) 60°
c) 65°
d) 70°
Answer:
c) 65°
Question 19: Which property ensures that triangle construction is possible with given lengths?
a) Pythagoras theorem
b) Parallel postulate
c) Triangle inequality
d) Midpoint theorem
Answer:
c) Triangle inequality
Question 20: A triangle cannot have two ___ angles.
a) Acute
b) Right
c) Obtuse
d) Both b and c
Answer:
d) Both b and c
Question 21: In a right triangle, if one acute angle is 35°, the other is ___.
a) 35°
b) 45°
c) 55°
d) 65°
Answer:
d) 55°
Question 22: Which of these triangles always has all equal angles?
a) Scalene
b) Isosceles
c) Equilateral
d) Right-angled
Answer:
c) Equilateral
Question 23: The angle opposite the longest side of a triangle is always ___.
a) The smallest
b) The largest
c) 90°
d) Equal to one other angle
Answer:
b) The largest
Question 24: The altitude of an equilateral triangle of side 6 cm is ___.
a) 2 cm
b) 3√3 cm
c) 6 cm
d) 4√3 cm
Answer:
b) 3√3 cm
Question 25: A triangle with sides 5 cm, 5 cm, and 8 cm is ___.
a) Equilateral
b) Isosceles
c) Scalene
d) Right-angled
Answer:
b) Isosceles
Question 26: Which of the following can be the measures of a triangle’s angles?
a) 60°, 60°, 60°
b) 100°, 40°, 40°
c) 90°, 90°, 0°
d) Both a and b
Answer:
d) Both a and b
Question 27: If two sides of a triangle are 7 cm and 24 cm, the third side must be greater than ___.
a) 7 cm
b) 17 cm
c) 24 cm
d) 31 cm
Answer:
b) 17 cm
Question 28: The number of distinct medians a triangle has is ___.
a) 1
b) 2
c) 3
d) 4
Answer:
c) 3
Question 29: A triangle cannot be constructed with sides ___.
a) 4 cm, 5 cm, 6 cm
b) 7 cm, 10 cm, 20 cm
c) 8 cm, 15 cm, 17 cm
d) 6 cm, 6 cm, 6 cm
Answer:
b) 7 cm, 10 cm, 20 cm
Question 30: The sum of the exterior angles of any polygon is ___.
a) 90°
b) 180°
c) 270°
d) 360°
Answer:
d) 360°
Question 31: The perpendicular from the vertex of a right-angled triangle to the hypotenuse divides it into ___.
a) Equal halves
b) Two smaller right triangles
c) Two obtuse triangles
d) Two equilateral triangles
Answer:
b) Two smaller right triangles
Question 32: If all angles of a triangle are equal, each measures ___.
a) 45°
b) 60°
c) 90°
d) 120°
Answer:
b) 60°
Question 33: Which triangle has all its sides of different lengths and all its angles different?
a) Scalene
b) Isosceles
c) Equilateral
d) Right-angled
Answer:
a) Scalene
Question 34: If one exterior angle of a triangle is 150°, then the sum of the two opposite interior angles is ___.
a) 30°
b) 90°
c) 120°
d) 150°
Answer:
d) 150°
Question 35: The sum of all three altitudes of a triangle is always ___.
a) Constant for all triangles
b) Equal to its perimeter
c) Different for different triangles
d) Equal to 180°
Answer:
c) Different for different triangles
Fill in the blanks on A Tale of Three Intersecting Lines for Class 7 Maths
1. The sum of the three interior angles of any triangle is always ___.
Answer:
180°
2. A triangle cannot be formed if the sum of any two sides is ___ the third side.
Answer:
less than or equal to
3. The exterior angle of a triangle is equal to the sum of its two ___ interior angles.
Answer:
opposite
4. A triangle with all three sides of equal length is called an ___ triangle.
Answer:
equilateral
5. A triangle with two equal sides is called an ___ triangle.
Answer:
isosceles
6. A triangle with all three sides of different lengths is called a ___ triangle.
Answer:
scalene
7. The angle opposite the longest side of a triangle is always the ___ angle.
Answer:
largest
8. The sum of any two sides of a triangle is always ___ than the third side.
Answer:
greater
9. A triangle cannot have more than one ___ angle.
Answer:
right or obtuse
10. If one angle of a triangle is 90°, the triangle is called a ___ triangle.
Answer:
right-angled
11. If all the three angles of a triangle are less than 90°, the triangle is called an ___ triangle.
Answer:
acute-angled
12. If one angle of a triangle is greater than 90°, the triangle is called an ___ triangle.
Answer:
obtuse-angled
13. In an equilateral triangle, each angle measures ___.
Answer:
60°
14. If two angles of a triangle are equal, the sides opposite them are also ___.
Answer:
equal
15. The sum of the exterior angles of any polygon is always ___.
Answer:
360°
16. The difference between the sum of any two sides of a triangle and the third side must always be ___ than zero.
Answer:
greater
17. A triangle with angles 40°, 60°, and 80° is classified as an ___ triangle.
Answer:
acute-angled scalene
18. The perpendicular drawn from a vertex of a triangle to the opposite side is called an ___.
Answer:
altitude
19. A line segment joining a vertex of a triangle to the midpoint of the opposite side is called a ___.
Answer:
median
20. A triangle with angles 120°, 30°, and 30° is classified as an ___ triangle.
Answer:
isosceles obtuse-angled