Compute the area bounded by the lines x + 2y = 2, y – x = 1 and 2x + y = 7.
Given;
The lines x + 2y = 2
x = 2 – 2y …. (1)
y – x = 1
⇒ x = y - 1 …. (2)
and 2x + y = 7 …. (3)
Equate the values of x from 1 and 2 to get,
2 – 2y = y – 1
2+1 = y + 2y
3 = 3y
y = 1
put the value of y in (2) to get,
x = 1 -1
= 0
So, intersection point is (0,1).
By solving these equations, we get the points of intersection as (0,1), (2,3) and (4,-1).
Area of the region bounded by the curve y=f(x), the x-axis and the ordinates x=a and x=b, where f(x) is a continuous function defined on [a,b], is given by .
Required area
=3 + (24 − 12) − (12 − 3) = 6 sq.units