Question 1: Calculate the third angle of a triangle if two angles are 65° and 45°.

Answer: 70

Question 2: In a triangle, one angle is 90°, and another is 40°. What is the measure of the third angle?

Answer: 50

Question 3: Construct a triangle where two angles are 70° and 60°. Use the grid to draw this triangle and label the angles.

Answer: The third angle is 50°; draw triangle with angles 70°, 60°, and 50°.

Question 4: A triangle has angles in the ratio 2:3:4. Find the measure of each angle.

Answer: 30°, 45°, and 60°

Question 5: A triangle has one angle of 85°. The other two angles are equal. Find the measure of each of the equal angles.

Answer: 45

Question 6: In a triangle, if one angle is 60°, and the other two are supplementary, what are the measures of the other two angles?

Answer: 120° and 60°

Question 7: A student claims that the sum of angles in any triangle is always 180°. Is this true? Explain briefly.

Answer: Yes, it is true for Euclidean triangles as per the angle sum property.

Question 8: A triangle has one angle of 50° and another of 65°. The third angle is unknown. Calculate it.

Answer: 65

Question 9: Challenge: Construct an isosceles triangle where the base angles are 40°. Use the grid to draw and label the triangle.

Answer: Base angles are 40°, apex angle is 100°.

Question 10: Identify and correct the mistake in this statement: 'All triangles with a 90° angle have angles that sum to 180°, but one of the angles can be more than 90°.'

Answer: Incorrect; the third angle must also be less than 90° because the sum is 180°.

Question 11: A triangle has angles of 80°, 60°, and a missing angle. Confirm whether these can be angles of the same triangle.

Answer: Yes, missing angle is 40°.