Consider this option:
1. rule: Circle is the locus of the points which are on the same distance from the given point. Common view of the equation is: (x-a)²+(y-b)²=r², where r - the distance from the given point to the described locus, a&b - coordinates of the given point.
2. using item 1:
(x+2)²+(y-1)²=3² or (x+2)²+(y-1)²=9.
Answer:
16 + 3n
Step-by-step explanation:
a = 19 ; common difference = 22 - 19 = 3
a(n) = a + (n -1 ) *d
= 19 + (n-1)*3
= 19 + 3n - 3
= 16 + 3n
In 2 years theirs 17520 in total!
