X*y=72
x = 5y-2
x=72/y
72/y=5y-2
72=5y^2-2y
5y^2 -2y - 72 = 0
(5y+18)(y-4)=0
y = -18/5 discard
or y = 4
4x=72
x=18
(18,4)
        
             
        
        
        
Answer:
The radius of circle B is 6 times greater than the radius of circle A
The area of circle B is 36 times greater than the area of circle A
Step-by-step explanation:
we have
<em>Circle A</em>

The radius of circle A is
 -----> the radius is half the diameter
 -----> the radius is half the diameter
<em>Circle B</em>

Compare the radius of both circles


The radius of circle B is six times greater than the radius of circle A
Remember that , if two figures are similar, then the ratio of its areas is equal to the scale factor squared
All circles are similar
In this problem the scale factor is 6
so

therefore
The area of circle B is 36 times greater than the area of circle A
 
        
             
        
        
        
1.=(2/3,0) 2.=(-3,0) 3.=-10 4.=need a graphing calc 5.=need a graphing calc