Answer:
The diameter of the target is 
Step-by-step explanation:
we know that
In this problem the distance from the center of an archery target to the outside edge of the target is equal to the radius of the target
so

Remember that
The diameter is two times the radius

substitute

I have to assume that you mean it is a similar rectangle, since a triangle can not be similar to a rectangle. In that case the original measurements are 4x4.5.
By doubling them, you get a rectangle with the measurements of 8x9 and thus the area is 72
Attach the numbers What number