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:
b
Step-by-step explanation:
b just honestly looks right and its my lucky letter so yaa...
I think the answer is y=10
Answer:
Step-by-step explanation:
Half life is the time taken by a radioactive substance to reduce of half of its original size
If the half life of radium is 1600, this means that the original radioactive substance N0 have reduced to N0/2 after 1600 years
if we are given N0 = 1000grams
The amount of the substance that will remain after 1600 years will be N0/2 i.e 1000/2 = 500g
<em>Hence 500 grams of radium will be left after 600years</em>
We can setup an equation for this.
Boys to Girls = 2:7
Boys = x
Girls = 250+x
Setup the ratio
x:(250+x) = 2:7
x / (250+x) = 2/7
7x = 500+2x
7x-2x = 500
x = 500/5 =100
There are 100 boys at the concert