CBSE - Constructions

1 Constructions 

To draw a pair of tange nts to a circle  which are  incline d to e ach othe r at an angle  of 45° it is re quire d to draw tange nts at the  e nd point of those  two radii of the  circle , the  angle  be twe e n which is :

1) 105° 
2) 135°
3) 145°
4) 70°

2 Constructions 

The length of each side of an equilateral triangle of area 4Ö3 cm², is 

1) 8 cm
2) 4 cm
3) Ö3 / 4 cm
4) 3 cm

3 Constructions 

If the length of a median of an equilateral triangle is x cm, then its area is 

1) x² 
2) Ö3x² / 2
3) x² / Ö3
4) x² / 2 

4 Constructions 

 In the  given figure , triangle s ABC and DEF are  similar. The  are a of triangle  ABC is 9 sq. cm and the  are a of triangle  DEF is 16 sq. cm. If BC = 2.1 cm find the  length of EF.

1) 4.9 cm 
2) 6.8 cm
3) 2.8 cm
4) 9.4 cm

5 Constructions 

The length of the sides of ∆ABC are consecutive integers. If ∆ABC has the same perimeter as an equilateral triangle with a side of length 9cm, what is the length of the shor test side of ∆ABC? 

1) 8 
2) 6
3) 4
4) 10 

6 Constructions 

From the  given figure , find out what is AC : AB.

1) 2 : 3 
2) 5 : 3
3) 3 : 2
4) 3 : 5

7 Constructions 

The sides of a triangle are 16 cm, 30 cm, 34 cm. Its area is

1) 225 cm² 
2) 225Ö3  cm²
3) 225Ö2 cm²
4) 240 cm² 

8 Constructions 

  PQ is a tangent to a circle  with centre  O at the point P. If triangle  OPQ is an isosceles triangle , then angle  OQP is equal to
 

1) 30° 
2) 90°
3) 45°
4) 60°

9 Constructions 

A square and an equilateral triangle have equal perimeters. If the diagonal of the square is 1272 cm, then area of the triangle is 

1) 24Ö2  cm² 
2) 24Ö3 cm²
3) 48Ö3  cm²
4) 64Ö3  cm²

10 Constructions 

   If TP and TQ are  two tangents to a circle  with centre  O so that angle  POQ = 110° then angle PTQ is equal to

1) 60° 
2) 80°
3) 70°
4) 90°