Hello from MrBillDoesMath!
Answer:
Area = 28,243 approximately (assuming that 7 1 3 cm meant 713 cm)
Discussion:
See attachment. The length of the rectangle (shown as "L") is twice the width (shown as "w"). This means
L = 2w (A)
We are also told the perimeter (the sum of the side lengths of the rectangle) is 713 cm or
L + w + L + w = 713 => add common terms
2L + 2w = 713.
Substituting (A), above, into this equation gives:
2L + 2w = 713
2 (2w) + 2w = 713 =>
4w + 2w = 713 => combine common terms
6w = 713 => divide both sides by 6
w = 713/6
The original question was to find the area of the rectangle.
A = L w => using (A) above
A = (2w) w => combine common terms
A = 2w^2 => as w = 713/6
A = 2 (713/6)^2 => calculator time
A= 2 (14121.4) approximately
A = 28,243 approximately
Hope this didn't confuse you but the problem has several elements that one needs to deal with.
Thank you,
MrB