SECTION 8.2

Question 1

What is the equation of a circle?

Answer 1

(x - h)² + (y - k)² = r²

Question 2

What is the distance formula?

Answer 2

square root of (x₁ - x₂)² + (y₁ - y₂)²

Question 3

What is the midpoint formula?

Answer 3

(x₁ + x₂)/2, (y₁ + y₂)/2

Question 4

What are the equation, foci, vertices, and eccentricity of a horizontal ellipse?

Answer 4

Equation: (x - h)²/a² + (y - k)²/b² = 1, a > b
Foci: (h±c, k)
Vertices: (h±a, k)
Eccentricity: c / a

Question 5

What are the equation, foci, vertices, and eccentricity of a vertical ellipse?

Answer 5

Equation: (x - h)²/b² + (y - k)²/a² = 1, a > b
Foci: (h, k±c)
Vertices: (h, k±a)
Eccentricity: c / a

Question 6

How do you solve for the variable “C” in ellipses?

Answer 6

c = square root of a² - b²