QUADRATIC EQUATIONS
?
?
800m2
1. Is it possible to design a rectangular mango grove whose length is twice its breadth, and the area is 800m2 ? If so, find its length and breadth.
Sol.
Let the breadth of mango grove = x m
∴ Length of mango grove
According to the given condition,
∴
Area of rectangular mango grove = 800 m2
( ) ( )
=
800
∴
2x2
=
800
∴
x2
=
400
∴
x
=
± 20
∴
x
=
20
or x = - 20
But breath cannot be negative,
So neglecting x
=
-20, we get
∴
x
=
20
and 2x =
2 × 20 = 40
Breadth of mango grove is 20 m and length of mango grove is 40m.
It is given that ……
In a comparative statement whatever comes later is taken as ‘x’
x
2x
=
2x m
Yes it is possible to design a rectangular mango grove whose length is twice its breadth and the area is 800m2
What we need to find ?
Area of a rectange = Length × Breadth
EX 4.4 3