The Triangle and Its Properties
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Short Answer Questions(SAQs)
What are some of the facts of triangles?
- A triangle has three sides, three vertices and three angles.
- The sum of the three interior angles of a triangle is always 180°.
- The sum of the length of two sides of a triangle is always greater than the length of the third side.
What is the ‘Angle sum property’?
The angle sum property of a triangle says that the sum of its interior angles is equal to 180°.
What are some of the uses of triangles?
Triangles can be used to make trusses. Trusses are used in many structures, such as roofs, bridges and buildings.
MCQs
1. What is the sum of all interior angles of a triangle?
(a) 90°
(b) 120°
(c) 180°
(d) 360°
► (c) 180°
2. What is the measure of each angle in an equilateral triangle?
(a) 45°
(b) 60°
(c) 90°
(d) 120°
► (b) 60°
3. A triangle with one angle greater than 90° is called?
(a) Acute triangle
(b) Right triangle
(c) Obtuse triangle
(d) Equilateral triangle
► (c) Obtuse triangle
4. Which triangle has all sides of different lengths?
(a) Equilateral
(b) Isosceles
(c) Scalene
(d) Right
► (c) Scalene
5. What do we call a triangle that has two equal sides?
(a) Scalene
(b) Isosceles
(c) Equilateral
(d) Right
► (b) Isosceles
6. Which type of triangle includes a 90° angle?
(a) Acute triangle
(b) Right triangle
(c) Obtuse triangle
(d) Equilateral triangle
► (b) Right triangle
7. If one angle of a triangle is 90°, what is the sum of the other two angles?
(a) 45°
(b) 60°
(c) 90°
(d) 180°
► (c) 90°
8. Which rule must hold true for any triangle?
(a) All sides are equal
(b) The sum of any two sides is equal to the third
(c) The sum of any two sides is greater than the third side
(d) The angles are all 90°
► (c) The sum of any two sides is greater than the third side
9. Which type of triangle has all angles less than 90°?
(a) Right triangle
(b) Acute triangle
(c) Obtuse triangle
(d) Equilateral triangle
► (b) Acute triangle
10. A triangle has angles of 50°, 60°, and ___?
(a) 60°
(b) 80°
(c) 70°
(d) 90°
► (c) 70°
11. In an equilateral triangle, the sides are:
(a) All equal
(b) Two equal
(c) All different
(d) One equal to zero
► (a) All equal
12. The side opposite the right angle in a right triangle is called:
(a) Adjacent
(b) Hypotenuse
(c) Base
(d) Height
► (b) Hypotenuse
13. What is the smallest number of degrees a triangle can have as one of its angles?
(a) 1°
(b) 0°
(c) 30°
(d) 89°
► (a) 1°
14. Which of the following can form a triangle?
(a) 2 cm, 3 cm, 6 cm
(b) 4 cm, 4 cm, 8 cm
(c) 5 cm, 6 cm, 10 cm
(d) 7 cm, 8 cm, 9 cm
► (d) 7 cm, 8 cm, 9 cm
15. What is the name of a triangle with angles 30°, 60°, and 90°?
(a) Equilateral
(b) Isosceles
(c) Right-angled
(d) Scalene
► (c) Right-angled
16. What is the longest side in a right-angled triangle?
(a) Opposite
(b) Adjacent
(c) Base
(d) Hypotenuse
► (d) Hypotenuse
17. Can a triangle have more than one right angle?
(a) Yes
(b) No
(c) Only if it's isosceles
(d) Sometimes
► (b) No
18. Which triangle has exactly two equal angles?
(a) Equilateral
(b) Isosceles
(c) Scalene
(d) Right
► (b) Isosceles