Question

the cost of fencing a field @rs 5 per metre is rs 1920 . if semi perimeter is 48 cm find its area and all sides.( ans according to herons formula class 9)
pls help...
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Answer 1

Dear Student,

● Answer -

Area = l × b

l = 38.86 m

b = 15.14 m

● Explaination -

You haven't mentioned shape of the area, but from given information it seems to be rectangle.

Semiperimeter = l+b

48 = l + b

b = 48 - l

Area of field is -

Area = 1920 / 5

Area = 384 m^2

But we know,

Area = l × b

384 = l × (48-l)

384 = 48l - l^2

l^2 - 48l + 384 = 0

l = 38.86 m

Now,

b = 48 - l

b = 48 - 38.86

b = 15.14 m

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