Mathematics - Class ...

Q1.

Classify the triangles into acute, obtuse and right angled triangle with following angles:

a.   30°, 90°, 60°                       _________________________

b.   55°, 45°, 80°                       _________________________

c.   80°, 60°, 40°                       _________________________

d.   120°, 40°, 20°                     _________________________

e.   90°, 45°, 45°                       _________________________

f.    35°, 95°, 50°                       _________________________

Q2.

Classify triangles according to sides as equilateral, isosceles or scalene triangle.

a. 5cm, 3cm, 6cm                    _________________________

b. 7cm, 7cm, 7cm                    _________________________

c. 8cm, 8cm, 7cm                     _________________________

d. 9cm, 11cm, 10cm                 _________________________

e. 4cm, 5cm, 6cm                     _________________________

f. 4.5cm, 4.5cm, 5.5cm               _________________________

Q3.

If two angles of a triangle measures 50° and 60°. Find the measure of the third angle of the triangle.

Q1.

Can we have a triangle with the following angles and sides? Justify your answer with reason.

a.     50°, 90°, 60°            ______________________

________________________________________

b.   80°, 70°, 80°            _______________________

_________________________________________       

c.     8cm, 4cm, 4cm          _______________________                  

__________________________________________

d.    10cm, 5cm, 5cm         ________________________           

__________________________________________

Q2.

Find the third angle and mention the kind of triangle.

a. ∠A = 80°, ∠B = 40°, ∠C =?      _____________________________________________________

b. ∠A = 60°, ∠B = 90°, ∠C =?      _____________________________________________________

c. ∠A = 120°, ∠B = 35°, ∠C =?      _____________________________________________________

Q3.

The three angles of a triangle are in the ratio of 2:3:5. Find the measure of each angle of the triangle.

Q1.

Draw 3 non collinear points as L, M and N on a paper. Now join LM, MN and NL. Name the figure you get and answer the following question:

a.   Name :  ___________________

b.     The side opposite to  ∠M   __________________

c. The angle opposite to side LM   __________________       

d.   Vertex opposite to side NM   _________________            

e.   The side opposite to angle M  __________________            

Q2.

Fill in the blanks:

a. The sum of 3 angles of a triangle equals to ____________.

b. The sum of the lengths of any two sides of a triangle is ______________ than the length of the third side.

c. In an isosceles triangle, the angles opposite to the equal sides are ____________.

d. An equilateral triangle is also an ______________________ triangle.

e. Triangles are classified on the basis of __________ and on the basis of _________.

Q3.

If one of the acute angle of a right angled triangle is 42°. Find out the other acute angle of the triangle.