Samantha read 6 pages in 12 minutes
Answer:
Step-by-step explanation:
The general equation of a circle can be expressed as (x-a)²+(y-b)² = r² where (a,b) is the centre of the circle and r is the radius.
To show that the equation x² + y² +6y + 2 = 0 represents a circle, we need to write it in the format above using the completing the square method.
Given x² + (y² +6y) + 2 = 0
First we need to complete the square of the square in parenthesis by adding the square of half of the coefficient of y i.e 
to the equation and adding the constant to the other side of the equation as well.
x² + (y² +6y) + 2 = 0
<em>Hence the equation represents a circle with centre C at (0, -3) and radius of √7</em>
Did you mean :
f(x) = x² - 2x, find x = -3
f(-3) = (-3)² - 2(-3)
f(-3) = 9 + 6
f(-3) = 15
You have posted 2 separate questions here. Please, next time, separate them with a blank line:
<span>A circle has an area of 81 3.14 units . what is the diameter in terms of 3.14?
I'd prefer you write this as
"</span><span>A circle has an area of 81 pi units . what is the diameter in terms of pi?
Area of a circle = A = pi*r^2. Note that r= diameter / 2. Here, the area is 81 pi square units, or 9^2 * pi square units, which means that the radius is 9 units. The diameter is then 2(9 units) = 18 units.
Your second question, separated from the first, is:
"</span><span>a circle has an area of 81 Pi square units what is the diameter of the circle?"
</span><span>
Use the following formula or formulas: d = 2*r; A = pi*r^2; A = pi*(d/2)^2. Find r first, and then find d.
</span>
Hi there
Total paid
31×12
=372
finance charge
372−295
=77
Hope it helps
