It is 3y because of the calculation being equivalent
        
             
        
        
        
<u>Answer:</u>
The correct answer option is B. both a function and a relation.
<u>Step-by-step explanation:</u>
We are given a from from which we can see that for each input we have exactly one output.
This means that we have a function because each element in the domain is matched with exactly one element in the range.
It is also a relation since each input related to the out put in some way.
Therefore, the correct answer option is B. both a function and a relation,
 
        
             
        
        
        
<span>Length = l</span>
<span>
Width = w</span>
<span>
Perimeter = p = 100
</span>
<span>Perimeter of rectangle = 2(l+w)</span>
<span>
100 = 2 (4w + w)</span>
<span>
100 = 2(5w)</span>
<span>
100 = 10w</span>
<span>
100/10 = w</span>
<span>
10 = w</span>
<span>
w =  10
Area of rectangle = length * width</span>
<span>
a = l*w</span>
<span>
a = 4w*w</span>
<span>
a = 4w^2............(1)</span>
<span>
Put the value of w in (1)</span>
<span>
a = 4(10)^2</span>
<span>
a= 4(100)</span>
<span>
a = 400 yd^2</span>
 
        
             
        
        
        
The relation of t as in to what?
        
             
        
        
        
I can't see the options, but you would need to multiply (4x - 2y = 7) by 3, and (3x - 3y = 15) by 4 so that you get 12x in both equations. Then when you subtract, you eliminate 12x. I hope this helps!