CUET Preparation Today
CUET
General Test
Quantitative Reasoning
Geometry
In the given figure, in triangle ABC, BC = 8 cm, AC = 9 cm and AB = 2 cm. AE = 24 cm, BF = 32 cm and DC = 27 cm. What is the ratio of the area of triangle DEA and area of triangle DLF ? |
2 : 3 4 : 9 1 : 5 4 : 3 |
4 : 9 |
Let, ∠DAE = θ then, ∠BAC = 180° - θ and let ∠FCD = ∝ then, ∠BCA = 180° - ∝ ∴ Ratio of area of \frac{ΔDAE}{ΔABC} = \frac{\frac{1}{2}× 18 × 24 × sinθ}{\frac{1}{2} × 12 × 9 × sin (180 - θ)} \frac{ΔDAE}{ΔABC} = \frac{4sinθ}{sinθ} = \frac{4}{1} \frac{ΔDCE}{ΔABC} = = \frac{9sin∝}{sin∝} = \frac{9}{1} Ratio of area, ΔDAE : ΔABC : ΔDCF 4 : 1 1 : 9 4 : 1 : 9 ∴ Ratio of area \frac{ΔDAE}{ΔDCF} = \frac{4}{9} = 4 : 9 |