<span>circumference = 2 π r
138.16 = 2 π r
138.16/2π = 2π/2π r
21.98884694 =r
D</span><span>iameter = r X 2
</span>Diameter = <span><span>21.98884694</span> X 2</span>
Diameter = 43.97769388
Applying a dilation centered at the origin with scale factor
has the effect of multiplying both coordinates of a point by
:

So, in your case, the coordinates of the points double:

Answer:
b = 12.6
Step-by-step explanation:
a*2 + b*2 = c*2
6*2 + b*2 = 14*2
36 + b*2 = 196
Subtract 36 from both sides
36 + b*2 = 196
-36 -36
b*2 = 160
Find the square root of both
b = 12.64911064 or 12.6