The radius is the distance from the center to any point. The distance from (2,1) to (0,1) is of course 2. The general formula for a circle with radius r and center (a,b) is

In our case we get
Answer:

Step-by-step explanation:
We need to find the distance between two points i.e. (−5,−1) and (−3,−8).
It can be calculated using distance formula as follows :

We have, x₁ = -5, x₂ = -3, y₁ = -1 and y₂ = -8
Put all the values,

So, the distance between the points is equal to 
Answer:
6/2(1+2)
the 2 will divide 6 or go into 6 ,how many times, 3 times because 2*3=6
next 1+2=3
therefore 3(3) =9
Moving from a to b, the x component of the desired vector is 7-(-9) = 16, and
the y component is 3-9 = -6.
So the vector from a to b is <16,-6>, and the magnitude is
sqrt(16^2 + (-6)^2 ), applying the Pythagorean Theorem.
The average height of the fence is 2 m; its length is 20π m. So, its 2-sided area is
A = 2*(2 m)*(20π m) = 80π m² ≈ 251 m²
At 1 L/(100 m²), it will take 2.51 L of paint to paint both sides.