It makes your life easier.One way is by just adding a 0 after the number.
Ex 2*10 is 20 see what I mean.
As the diameter is 18, a radius is half the diamater ergo the radius is 9.
Use the circumference formula:

So, adapted it would be:
2 * π * 9 which would be 56.7.
The circumference is 57m.
Hope this helps!
Answer:
(2.405, 1.537)
Step-by-step explanation:
When you graph these, they intersect at (2.405, 1.537).
You can use desmos as a graphing calculator, it is extremely helpful.
Hope this helps!
Step-by-step explanation:
8x + x² - 2y + y² - 64 = 0
(x + 4)² + (y - 1)² - 81 = 0
(x + 4)² + (y - 1)² = 81
Hencr the center is (-4,1) and the radius is 9.