ABC is right angled at A AD is perpendicular to BC. If AB = 5 cm, BC = 13 cm and AC = 12 cm. Find the area of 
ABC. Also find the length of AD.
It is given in the question that,
AB = 5 cm
BC = 13 cm
AC = 12 cm
We know that,
Area of triangle = 
× Base × Height
∴ Area of 
= 
× 5 × 12
= 
× 60
= 30 cm2
Area of triangle = 
× AD × BC
30 = 
× AD × 13
60 = AD × 13
AD = 
= 4.6 cm
∴ Area of 
ABC = 30 cm2
Length of AD = 4.6 cm
20