Question 940428
For a rectangle, Area = length * breadth
Perimeter = 2(length + breadth)

Let l rep. length, breadth reo. w
From statement Area, l*w=18.86 eqn1
and Perimeter, 2(l+w)=21
expanding
2*l+2*w=21 ----eqn2
Solving eqn1 and eqn2 simultaneously

*[invoke linear "l", "w", 1, 1, 18.86, 2, 2, 21]

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