Multiple choice

A circle with center (- 3, - 4) is tangent to the x - axis in the standard (x, y) coordinate plane. What is the radius of this circle?

  1. 3

  2. 4

  3. 5

  4. 9

  5. 16

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A circle tangent to the x-axis has a radius equal to the absolute value of the y-coordinate of its center. Center is (-3, -4), so radius = |-4| = 4.

AI explanation

The distance from the center to the x-axis is equal to the absolute value of its y-coordinate, which is |-4| or 4. Since the circle is tangent to the x-axis, this distance represents the radius of the circle. Therefore, the radius is 4.