Practice the questions given in the worksheet on properties of triangle.
1. Fill in the banks:
(i) Triangle is formed by joining three ______________ points.
(ii) A point where two sides of a triangle meet is known as ______________ of a triangle.
(iii) Each angle of an equilateral triangle is of ______________ measure.
(iv) A ______________ triangle has one angle of 90°.
(v) A triangle has ______________ vertices and ______________ sides.
(vi) In an obtuse triangle, the remaining two angles are ______________
(vii) The sum of the measure of three angles of a triangle is ______________
(viii) A triangle whose two sides are of equal length is known as ______________ triangle.
2. Which of the following cannot be the measure of three angles of a triangle?
(i) ∠A = 60°, ∠B = 60°, ∠C = 60°
(ii) ∠A = 70°, ∠B = 20°, ∠C = 100°
(iii) ∠A = 90°, ∠B = 90°, ∠C = 90°
(iv) ∠A = 72°, ∠B = 30°, ∠C = 78°
3. Find the measure of the third angle of a triangle:
(i) ∠A = 60°, ∠B = 60°
(ii) ∠A = 70°, ∠B = 80°
(iii) ∠A = 90°, ∠B = 10°
(iv) ∠A = 95°, ∠B = 25°
4. Look at the triangle given below and answer the following:
(i) What is the measure of ∆ABC?
(ii) What type of triangle ∆ABC?
(iii) What type of triangle ∆PQR?
(vi) What type of triangle ∆LMN?
(v) What is the measure of ∠L?
Answers for the worksheet on properties of triangle are given below.
1. (i) non collinear
(v) three, three
(viii) isosceles triangle
2. (ii) (iii)
3. (i) 60°
4. (i) 70°
(ii) acute angled triangle
(iii) isosceles triangle
(vi) equilateral triangle