(a)

(b)we have 4 terms in this expression.
(c)+12 is the leading coefficient in

(d) constant is -45
Answer:
(x-1)²+(y-3)²=65
Step-by-step explanation:
the common view of the equation of a circle is:
a) (x-a)²+(y-b)²=r², where (a;b) - the centre of the required circle, r - the radius of the required circle;
b) using the coordinates of the endpoint of the given diameter it is possible to calculate the coordinates of the centre of the required circle and its radius²:
the coordinate x of the required circle is: (9-7)/2=1;
the coordinate y of the required circle is: (2+4)/2=3.
the radius² of the required circle is:
r²=0.25*[(9- -7)²+(2-4)²]=0.25*260=65.
c) after the substitution the values of 'a'; 'b' and 'r²' into the common equation of the circle:
(x-1)²+(y-3)²=65.
PS. additional: the given points (9;2) and (-7;4) belong to the final equation, if to substitute their coordinates into it.
The suggested way of solution is not the only one.
Answer:
The y-coordinate of point A is
.
Step-by-step explanation:
The equation of the circle is represented by the following expression:
(1)
Where:
- Independent variable.
- Dependent variable.
,
- Coordinates of the center of the circle.
- Radius of the circle.
If we know that
,
and
, then the equation of the circle is:
(1b)
Then, we clear
within (1b):

(2)
If we know that
, then the y-coordinate of point A is:


The y-coordinate of point A is
.
Answer:
-10 is the second term.
Step-by-step explanation:
After the first term each term is obtained from the previous one by adding 10.
c(1) = -20
so c(2) = -20 + 10
= -10.