Question
In a cyclic quadrilateral ABCD, where AB = 7 cm, BC = 8
cm, CD = 9 cm, and DA = 10 cm, find the length of the diagonal AC if the angle between AB and DA is 60°.Solution
Using the cosine rule in triangle ACD: AC² = AD² + CD² - 2 × AD × CD × cos 60°, AC² = 10² + 9² - 2 × 10 × 9 × 1/2, AC² = 100 + 81 - 90, AC² = 91, AC = √91 ≈ 9.53 cm. Answer: c) 9.5 cm.
In the following questions, a sentence is highlighted and given in Active Voice. Choose the correct option that converts it into Passive Voice.
Choose the option that is the passive form of the sentence.
The detective found the lost necklace.
It may not contain all the information.
Select the correct active form of the given sentence.
The light was switched off by her before sleeping.
Choose the correctly spelt word.
Shayan was practicing football.
 Groups of four words are given. In each group one word is rightly spelt. Find the rightly spelt word.
 (a)  Translucent      (b)  ...
Select the correct passive form of the given sentence.Â
Our advocate is arguing the case very effectively.
Select the correct active \passive form of the given sentence.
Everyone thinks that the educational system is bad in India.
Select the correct passive form of the given sentence.
Manu will tell her later.
