Practicing Success
In ΔABC, F and E are the points on sides AB and AC, respectively, such that FE ll BC and FE divides the triangle in two parts of equal area. If AD ⊥ BC and AD intersects FE at G, then GD : AG = ? |
1 : \(\sqrt {2}\) (\(\sqrt {2}\) + 1) : 1 (\(\sqrt {2}\) - 1) : 1 3\(\sqrt {2}\) : 1 |
(\(\sqrt {2}\) - 1) : 1 |
Similar triangle Theorem applied ΔAGE ∼ ΔADC (\(\frac{AG}{AD}\))2 = \(\frac{ar.\;of\;ΔAGE}{ar.\;of\;ΔADC}\) = \(\frac{1}{2}\) \(\frac{AG}{AD}\) = \(\frac{1}{\sqrt {2}}\) [Area of ΔAEF = area of quadrilateral FECD, similarly; [Area of ΔAGE = area of quadrilateral GECD = 1 Unit] GD = AD - AG = \(\sqrt {2}\) - 1 \(\frac{AG}{GD}\) = \(\frac{1}{\sqrt {2} - 1}\) GD : AG = ( \(\sqrt {2}\) - 1) : 1 |