In the figure, (bigtriangleup) ABC are in adjacent planes. AB = AC = 5cm, BC = 6cm and o then AE is equal to
-
A.
3(sqrt{2}) -
B.
2(sqrt{3}) -
C.
(frac{sqrt{3}}{2}) -
D.
(frac{2}{sqrt{3}})
Correct Answer: Option B
Explanation
BC = 6 : DC = (frac{6}{2}) = 3cm
By construction o(90o + 60o) = 180o – 150o
= 30o(angle on a strt. line)
From rt 2 = 52 – 32
= 25 – 9 = 6
AD = 4
From
(frac{x}{sin 60^o}) – (frac{4}{sin 90^o})
sin 90o = 1
sin 60o = (frac{sqrt{3}}{2})
x = 4sin 60o
x = 3 x (frac{sqrt{3}}{2})
= 2(sqrt{3})