Question

A triangular field has dimensions 21m by 52m by 47m.

1. calculate the area of the field to the nearest m². 
2. calculate the length of a straight ditch dug from the largest angle meeting the opposite side at right angles. 

Answer 1

1. 
   
   Area
   S=½(47+21+52) =60
   A= √(60(60−52)(60−47)(60−21))
     = √(60×8×13×39) =493.3m² 
   =493m² 
2. ½ × 52 ×h =493  
      h= 493 × 2 = 18.96m
               52