Coordinate Geometry and Circles Flashcard Review

Front

What can be said about two lines with opposite reciprocal slopes?

Back

They are perpendicular.

Front

What is the area of a shaded sector in a circle with a diameter of 12 cm and an angle of 24°?

Back

49.0 cm².

Front

Write the equation of a circle with a diameter having endpoints at (–4, 1) and (2, 9).

Back

(x + 1)² + (y – 5)² = 25.

Front

What is the formula for the area of a rectangle?

Back

Area = length × width.

Front

What is the area of a rectangle with a length of 8 units and a width of 8 units?

Back

64.0 square units.

Front

What is the relationship between the slopes of two parallel lines?

Back

The slopes of parallel lines are equal.

Front

What is the relationship between the slopes of two perpendicular lines?

Back

The slopes of perpendicular lines are opposite reciprocals.

Front

How do you find the center of a circle given its diameter endpoints?

Back

The center is the midpoint of the endpoints.

Front

What is the formula for the area of a circle?

Back

Area = πr², where r is the radius.

Front

If a circle has a radius of 5 cm, what is its area?

Back

78.5 cm² (using π ≈ 3.14).