In a ∆ABC,AB=15cm,BC=13cm and AC=14cm.Find the area of ∆ABC and hence its altitude on AC.

In a ∆ABC,AB=15cm,BC=13cm and AC=14cm.Find the area of ∆ABC and he

1.	In a ∆ABC,AB=15cm,BC=13cm and AC=14cm.Find the area of ∆ABC and hence its altitude on AC.
Answer» hi I am boss Hello I am Ankita I boss of 9class In ∆ABC, AB = 15 cm , BC = 13 cm and AC = 14 cm.By Heron\'s formula ,S = ( A + B + C ) / 2S = ( 15 + 13 + 14 ) / 2S = 42 / 2S = 21\xa0Now, area of triangle= √S (S–A) (S–B) (S–C)= √21 (21–15) (21–13) (21–14)= √21 (6) (8) (7)= √7056= 84 cm2Again,area of triangle = 1/2×base×altitude=84 cm21/2×14×altitude = 847 × altitude=84altitude = 84/7Altitude = 12cmTherefore, the area of ∆ABC is 84cm² and its altitude on AC is 12 cm.\xa0