In the figure below, some dimensions of a hut have been marked. Findthe other dimensions (marked ?) of the hut correctly up to one placeof decimal.
Solution:
In right angled ΔPQR,
∠ P = 90°
∠ PQR = 20°
sec θ = hypotenuse / adjacent
sec 20° = QR / PQ
1.0642 = QR / 3
QR = 1.0642 × 3
= 3.1926
QR = ST = 3.2 units
In right angled Δ ACD,
∠ CAD = 42° 6'
cot 42° 6' = AD / DC
1.1067 = AD / 1.5
∴ AD = 1.5 × 1.1067
= 1.66 units
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