Plane Geometry
-  Two equal circles of radius 4 cm intersect each other such that each passes through the centre of the other. The length of the common chord is :
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                        View Hint View Answer Discuss in Forum According to question , we draw a figure of two equal circles of radius 4 cm intersect each other such that each passes through the centre of the other ,  
 OC = 2cm
 OA = 4cm
 ∴ AC = √OA² - OC²
 ∴ AC = √4² - 2² = √16 - 4Correct Option: BAccording to question , we draw a figure of two equal circles of radius 4 cm intersect each other such that each passes through the centre of the other ,  
 OC = 2cm
 OA = 4cm
 ∴ AC = √OA² - OC²
 ∴ AC = √4² - 2² = √16 - 4
 AC = √12 = 2√3
 ∴ AB = 4√3cm
-  At least two pairs of consecutive angles are congruent in a _____.
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                        View Hint View Answer Discuss in Forum As per the given in question , we draw a figure cyclic trapezium ABCD  
 In an isosceles trapezium,
 AB || CD ; AD = BC
 AC = BD
 The angles of base are equal. i.e.Correct Option: BAs per the given in question , we draw a figure cyclic trapezium ABCD  
 In an isosceles trapezium,
 AB || CD ; AD = BC
 AC = BD
 The angles of base are equal. i.e.
 ∠A = ∠B ; ∠C = ∠D ; ∠A + ∠D = ∠B + ∠C = 180°
-  ABCD is a trapezium in which AD || BC and AB = DC = 10 m. then the distance of AD from BC is :
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                        View Hint View Answer Discuss in Forum According to question , we draw a figure of trapezium ABCD in which AD || BC and AB = DC = 10 m  
 AE ⊥ BC; DF ⊥ BC
 ∴ ∠DCB = 45°
 In ∆ CDF,sin 45° = DF DC ⇒ 1 = DF √2 10 
 Correct Option: CAccording to question , we draw a figure of trapezium ABCD in which AD || BC and AB = DC = 10 m  
 AE ⊥ BC; DF ⊥ BC
 ∴ ∠DCB = 45°
 In ∆ CDF,sin 45° = DF DC ⇒ 1 = DF √2 10 ⇒ DF = 10 = 5√2 metre. √2 
-  If the parallel sides of a trapezium are 8 cm. and 4 cm., M and N are the mid-points of the diagonals of the trapezium, then length of MN is
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                        View Hint View Answer Discuss in Forum As per the given in question , we draw a figure cyclic trapezium ABCD in which M and N are the mid-points of the diagonals ,  
 The line segment joining the mid– points of the diagonals of a trapezium is parallel to each of parallel sides and is equal to half the difference of these sides.
 Here , AB = 8 cm. and CD = 4 cm∴ MN = 1 (AB - CD) 2 
 Correct Option: DAs per the given in question , we draw a figure cyclic trapezium ABCD in which M and N are the mid-points of the diagonals ,  
 The line segment joining the mid– points of the diagonals of a trapezium is parallel to each of parallel sides and is equal to half the difference of these sides.
 Here , AB = 8 cm. and CD = 4 cm∴ MN = 1 (AB - CD) 2 MN = 1 (8 - 4) cm. = 2 cm. 2 
-  ABCD is a cyclic trapezium with AD || BC. If ∠A = 105°, then other three angles are
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                        View Hint View Answer Discuss in Forum On the basis of question we draw a figure of trapezium ABCD with AD || BC ,  
 AD || BC
 In concyclic quadrilateral ABCD,
 ∠A + ∠C = 180°
 ⇒ 105° + ∠C = 180°
 ⇒ ∠C = 180° – 105° = 75°
 Again,
 ∠A + ∠B = 180°
 ⇒ 105° + ∠B = 180°Correct Option: AOn the basis of question we draw a figure of trapezium ABCD with AD || BC ,  
 AD || BC
 In concyclic quadrilateral ABCD,
 ∠A + ∠C = 180°
 ⇒ 105° + ∠C = 180°
 ⇒ ∠C = 180° – 105° = 75°
 Again,
 ∠A + ∠B = 180°
 ⇒ 105° + ∠B = 180°
 ⇒ ∠B = 180° – 105° = 75°
 ∴ ∠D = 180° – 75° = 105°
 
	