posted by leon .
triangle ABC is right angled at A. AD is perpendicularto BC. If AB= 5cm,BC= 13cm and AC=12 cm.find the area of triangle ABC. Also find the length of AD.
The area is (1/2)*5*12 = 30 cm^2
You get that from the two perpendicular legs, which form a base and height.
Since AD is the height h' from base b' = BC,
(1/2)*h'*13 = 30
h' = 60/13 = 4.615 = length of AD