Column I | Column II |
(a) A man goes 10m due east and then 20m due north. His distance from the starting point is ……m. | (p) 25√3 |
(b) In an equilateral triangle with each side 10cm, the altitude is …..cm. | (q) 5√3 |
(c) The area of an equilateral triangle having each side 10cm is …..cm2. | (r) 10√5 |
(d) The length of a diagonal of a rectangle having length 8m and breadth 6m is ….m. | (s) 10 |
The correct answer is: (a) – ……, (b)-……, (c)-……, (d)-…..,
Correct Answer:
(a) −(r)
Let the man starts from A and goes 10 m due east at B and then 20 m due north at C.
Then, in right-angled triangle ABC,
????????2 + ????????2 = ????????2
Hence, the man is 10 √3???? ???????????????? ???????????????? ????ℎ???? ???????????????????????????? ????????????????????.
(b) −(q)
Let the triangle be ABC with altitude AD.
In right-angled triangle ABC,
????????2 = ????????2 + ????????2
????????2 = 102 − 52
AD = √75 => 5√3 ????m
(c) – (p)
Area of an equilateral triangle with side,
(d) – (s)
Let the rectangle be ABCD with diagonals AC and BD.
In right-angled triangle ABC,
????????2 = ????????2 + ????????2
=> 82 + 62
=> 64 + 36
???????? = √100
=> 10 m