Find the area bounded by the lines y = 4x + 5, y = 5 – x and 4y = x + 5.

Given;

The lines y = 4x + 5, y = 5 – x and 4y = x + 5.



By solving these equations,


y = 4x + 5 …… (1)


y = 5 − x …… (2)


4y = x + 5 …… (3)


From (1) and (2);


4x + 5 = 5 − x


x = 0; y = 5 − x = 5


From (2) and (3);


4 (5 − x) = x + 5


x = 3; y = 5 − x = 2


From (1) and (3);


4 (4x + 5) = x + 5


x = −1; y = 4x + 5 = 1


we get the points of intersection as (0,5), (3,2) and (-1,1).


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







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