The shape of a farm is a quadrilateral. Measurements taken of the farm, by naming its corners as P, Q, R, S in order are as follows. l(PQ) = 170 m, l(QR)= 250m, l(RS) = 100 m, l(PS) = 240 m, l(PR) = 260 m.
Find the area of the field in hectare ( 1 hectare =10,000 sq.m)
Answers
Solution :-
PQRS is a quadrilateral. PQ = 170 m, QR 250 m, RS = 100 m, PS = 240 m, PR = 260 m
This question will be solved through Heron's formula of area of triangle.
There are two triangles in the quadrilateral PQRS.
These are Δ PQR and Δ PSR
In Δ PQR,
PQ = 170 m, QR = 250 m and PR = 260 m
Semi perimeter (s) = (a + b + c)/2
(170 + 250 + 260)/2
⇒ 680/2
s = 340 m
Area of triangle PQR = √340*(340 - 170)*(340 - 250)*(340 - 260)
⇒ √340*170*90*80
⇒ √416160000
⇒ 20400 sq m
In Δ PSR,
SR = 100 m, PS = 240 m and PR = 260 m
S = (a + b + c)/2
⇒ (100 + 240 + 260)/2
⇒ 600/2
⇒ 300 m
Area of triangle Δ PSR = √(300)*(300 - 100)*(300 - 240)*(300 - 260)
⇒ √300*200*60*40
⇒ √144000000
= 12000 sq m
Area of the quadrilateral PQRS = Area of Δ PQR + Area of Δ PSR
⇒ 20400 + 12000
= 32400 sq m
Area in hectares = 32400/10000
= 3.24 hectares
Answer.
Hi,
Answer: 3.24 hectare
Solution: since given figure is a quadrilateral,here by diagonal we can divide the quadrilateral into two triangles.
Here we are calculating the area of triangle by semi-perimeter formula ( Heron's formula),since obtained triangles are not necessarily right angle triangle.
For detailed solution find attachment .
hope it helps you.