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>
Answer:
78
Step-by-step explanation:
angle ACD + angle DCB = 180 (Angles on straight line)
4x + 2 + 3x + 3 = 180
7x + 5 = 180
7x = 180-5
7x = 175
x = 175 / 7
x = 25
angle DCB = 3x +3 = 3*25 + 3 = 75 +3 = 78
<h2>
Answer:</h2>
The surface area of a shape is the sum of the area of all of its faces. To find the area of a cylinder, you need to find the area of its bases and add that to the area of its outer wall. The formula for finding the area of a cylinder is A = 2πr2 + 2πrh.
<h2>
Step-by-step explanation:</h2>
- Surface area of a cylinder = 2πr 2 + 2πrh
- Volume of a cylinder = πr 2 h
- You need to know the radius and height to figure both the volume and surface area of a cylinder.
- Answers for volume problems should always be in cubic units.
- Answers for surface area problems should always be in square units.
Answer:
The vertical line test is a visual test used to determine whether or not a graph is a function. To perform this test, simply draw a straight vertical line multiple times on different parts of the graph.
If a vertical line intersects with the graph at one point, then it's a function.
If a vertical line intersects with the graph at multiple points, then it's not a function.
Examples:
