Advertisements
Advertisements
प्रश्न
Find AB and BC, if:

Advertisements
उत्तर
Let BC = x m
BD = BC + CD = (x + 20) cm
In ΔABD,
tan 30° = `"AB"/"BD"`
`(1)/(sqrt(3)) = "AB"/(x + 20)`
x + 20 = `sqrt(3)"AB"` ...(1)
In ΔABC
tan 60° = `"AB"/"BC"`
`sqrt(3) = "AB"/x`
x = `"AB"/sqrt(3)` ...(2)
From (1)
`"AB"/sqrt(3) + 20 = sqrt(3)"AB"`
AB + `20sqrt(3)` = 3AB
2AB = `20sqrt(3)`
2AB = `(20sqrt(3))/(2)`
AB = `10sqrt(3)`
AB = 17.32 cm
From (2)
x = `"AB"/sqrt(3)`
x = `(17.32)/sqrt(3)`
x = 10 cm
Therefore BC = x = 10 cm
Therefore, AB = 17.32 cm, BC = 10 cm.
APPEARS IN
संबंधित प्रश्न
Find angle 'A' if:

Find the lengths of diagonals AC and BD. Given AB = 60 cm and ∠ BAD = 60°.

In trapezium ABCD, as shown, AB // DC, AD = DC = BC = 20 cm and ∠ A = 60°. Find: length of AB

In trapezium ABCD, as shown, AB // DC, AD = DC = BC = 20 cm and A = 60°. Find: distance between AB and DC.

Use the information given to find the length of AB.

Find: BC
Find: AD

Find AB and BC, if:

Find PQ, if AB = 150 m, ∠ P = 30° and ∠ Q = 45°.

If tan x° = `(5)/(12)`,
tan y° = `(3)/(4)` and AB = 48 m; find the length of CD.
