Given:
The center of the circle = (-2,1).
Circle passes through the point (-5,3).
To find:
The equation of the circle.
Solution:
Radius is the distance between the center of the circle and any point on the circle. So, radius of the circle is the distance between the points (-2,1) and (-5,3).




On further simplification, we get


The standard form of a circle is:

Where, (h,k) is the center of the circle and r is the radius of the circle.
Substitute h=-2, k=1 and
.


Therefore, the equation of the circle is
.
Answer:
y = -
x + 1
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Here m = -
, then
y = -
x + c ← is the partial equation
To find c substitute (6, - 1 ) into the partial equation
- 1 = - 2 + c ⇒ c = - 1 + 2 = 1
y = -
x + 1 ← equation of line
In the second equation you are given what Y equals, which is (-5x - 3). You would use this equation and plug it into the y value given in the first equation where it says 2y and solve
That would be
3x - 2(-5x - 3) = -6
3x + 10x + 6 = -6
3x + 10x = -6 - 6
13x = -12
X = -12/13
Then if you want to solve for Y you can use any equation and plug in the x-value found.
I’m going to use equation 2.
Y = -5x - 3
Y = -5(-12/13) - 3
Y = 4.615 - 3
Y = 1.615
(-12/13, 1.615)
Therefore the x-value is -12/13 and the y-value is 1.615.
Answer:
Step-by-step explanation:
If the first floor of the Willis Tower is 21 feet high. and each additional floor is 12 feet high, then the floor heights as we move from one floor to another we keep increasing by 12feets and forms an arithmetic progression as shown;
21, (21+12), (21+12+12), ...
<em>21, 33, 45...</em>
a) To write an equation for the nth floor of the tower, we will have to find the nth term of the sequence using the formula for finding the nth term of an arithmetic sequence.
The nth term of an arithmetic sequence is expressed as 
a is the first term = 21
d is the common difference = 33-21 = 45-33 = 12
n is the number of terms
Substituting the given parameters into the formula;

<em>Hence the equation for the nth floor of the tower is expressed as </em>
<em></em>
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b) To get the height of the 65th floor, we will substitute n = 65 into the formula arrived at in (a)

<em>Hence the height of the 65th floor is 789feets.</em>