A 10 metre long ladder is placed against a wall. It is inclined

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A 10 metre long ladder is placed against a wall. It is inclined at an angle of 30° to the ground. The distance (in m) of the foot of the ladder from the wall is (Given √3 = 1.732)

AC = ladder = 10 metre
BC = ?
∠ABC = θ = 30°
From ∆ABC,

cos θ =	BC
	AC

⇒ cos 30° =	BC
	10

⇒	√3	=	BC
	2		10

⇒ BC =	10√3	= 5√3
	2

= 5 × 1.732 = 8.660 metre