Triangles
21 solved questions from Class 9 Mathematics, each with the full working. Tap any question to see the step-by-step solution.
- 1 What is the sum of all interior angles of a triangle? medium MCQ Angle Sum Property
- 2 What is the sum of interior angles of a quadrilateral? medium MCQ Polygon Angles
- 3 In a right triangle with legs 3 cm and 4 cm, find hypotenuse length. medium MCQ Pythagoras Theorem
- 4 How many tangents can be drawn to a circle from an external point? medium MCQ Tangents to Circle
- 5 What is the angle between a tangent and the radius at the point of contact? medium MCQ Tangent Properties
- 6 Two triangles are similar if their corresponding sides are in ____. medium MCQ Similar Triangles
- 7 Find the perimeter of a square with side length 6 cm. medium MCQ Perimeter of Square
- 8 What is the formula for area of a circle with radius r? medium MCQ Area of Circle
- 9 If diameter of a circle is 14 cm, what is its radius? medium MCQ Circle Definitions
- 10 State Pythagoras Theorem for a right-angled triangle. medium MCQ Pythagoras Theorem
- 11 What is the domain, range, or fundamental theorem introduced in 'Triangles' (Class 9 Mathematics)? medium MCQ Functions & Theorems
- 12 What is the derivative or integral formula associated with 'Triangles'? medium MCQ Calculus & Formulae
- 13 How do you find the solution set or optimum value in 'Triangles'? medium MCQ Problem Solving & Optimization
- 14 Find the perimeter of an isosceles triangle whose equal sides each measure 7 cm and whose base measures 10 cm. easy 1 mark Perimeter of a triangle
- 15 In a right triangle, the altitude drawn to the hypotenuse divides it into segments of 9 cm and 16 cm. Find the perimeter of the triangle. hard 4 marks Altitude to hypotenuse in a right triangle
- 16 Triangle ABC has sides 8 cm, 12 cm and 15 cm. Triangle DEF is similar to ABC and has two sides of 4 cm and 6 cm. Find the length of the third side of DEF. medium 3 marks Similarity of triangles
- 17 A right‑angled triangle has legs of length 6 cm and 8 cm. Find its perimeter. easy 1 mark Perimeter of a right triangle
- 18 In a triangle, the base is 14 cm and the height is 9 cm. What is its area? easy MCQ 1 mark Area of triangle
- 19 Find the area of a triangle whose base is 12,cm and height is 7,cm. easy 1 mark Area of triangle
- 20 Two triangles PQR and XYZ are similar. Triangle PQR has sides 7, 21 and 28 cm. Triangle XYZ is similar to PQR and has side XY = 14 cm. Find all the sides of triangle XYZ and its perimeter. hard 5 marks Similarity of triangles
- 21 In a right triangle, the lengths of the two legs are 5 cm and 12 cm. What is the length of the hypotenuse? easy MCQ 1 mark Pythagoras theorem