You can put this solution on YOUR website! the lenght of a triangle is twice the width. the perimeter is 84cm more than the width.
The problem should be as follows:
The lenght of a rectangle is twice the width.
The perimeter is 84cm more than the width.
Let the length be L cms
and let the width be B cms
Length = twice width
L=2B ----(1)
Perimeter 84 cms more than width
2(L+B) is 84 more than B
That is 2(L+B)-B =84
2L+2B-B=84
2L+B=84 ----(2)
Using (1)that is L=2B in (2)
2X(2B)+B=84
4B+B=84
5B=84
B=84/5=16.8 cms
L=2B =2X(16.8) =33.6 cms
Answer: Legth=33.6cms and width = 16.8 cms
Verification: Perimeter=2(L+B)= 2X(33.6+16.8)=2X(50.4)=100.8 cms
which is of course 84 more than 16.8 the width.
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