(21+39a)/20. Because they have to have the same denominator
Answer:
<h2>
70 
</h2>
Step-by-step explanation:
Shaded area:
Area of big rectangle - Area of small rectangle

Calculate the difference

Calculate the product

Calculate the difference

Hope this helps...
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The length of rectangular mosaic flag is 710 feet and width is 470 feet
Step-by-step explanation:
Let l be the length of the flag
and
w be the width
Then according to given statement
l = w+240
Perimeter = 2360 feet
The formula for perimeter is given by:

Putting values
![2360 = 2[w+240+w]\\\frac{2360}{2} = \frac{2[w+240+w]}{2}\\1180 = 2w+240\\1180-240 = 2w+240-240\\940 = 2w](https://tex.z-dn.net/?f=2360%20%3D%202%5Bw%2B240%2Bw%5D%5C%5C%5Cfrac%7B2360%7D%7B2%7D%20%3D%20%5Cfrac%7B2%5Bw%2B240%2Bw%5D%7D%7B2%7D%5C%5C1180%20%3D%202w%2B240%5C%5C1180-240%20%3D%202w%2B240-240%5C%5C940%20%3D%202w)
Dividing both sides by 2

The width is 470 feet
Now,

Hence,
The length of rectangular mosaic flag is 710 feet and width is 470 feet
Keywords: Perimeter, dimensions
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