10
Step-by-step explanation:
 
        
                    
             
        
        
        
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Explanation:</h2><h2>
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A circle is simply a curve made up of all the points that are the same distance from the center. This distance is called the radius of the circle. It's important to know that <em>all circles are similar to each other</em>, but what is similarity? It's simply, shapes are similar if we can turn one into the other by moving, rotating, flipping, or scaling. So every circle can match any other circle by moving it, rotating it, flipping it, or scaling it.
Then circles O and Q shown below are similar no matter what's the radii of them.
 
        
        
        
The rectangle maximum area will be A=9 square units with the length=3 and the width=3.
<h3>What is area of rectangle?</h3>
Area is defined as the space occupied by a plane or rectangle having length and width in two dimensional plane.
It is given that the perimeter of rectangle is P=12
So from the formula of perimeter of rectangle
2(L+W)=12
L+W=6
L=6-W
Now the area of rectangle will be 
A=LxW
A=(6-W)W
Now for maximum area we will find the derivative and equate to zero.




So the area will be 

Hence the rectangle maximum area will be A=9 square units with the length=3 and the width=3.
To know more about area of rectangle follow
brainly.com/question/25292087
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