Question

in circle d, which is a secant?

• $overline{ef}$
• $overline{dc}$
• $vec{ab}$
• $overleftrightarrow{gh}$

Explanation:

A secant is a line that intersects a circle at exactly two points.

• $\overline{EF}$ is a chord (a line segment with endpoints on the circle, not an infinite line).
• $\overline{DC}$ is a radius (a line segment from center to circle edge).
• $\overleftrightarrow{AB}$ is a tangent (only touches the circle at one point).
• $\overleftrightarrow{GH}$ is a line that crosses the circle at two points, fitting the definition of a secant.

Answer:

$\boldsymbol{\overleftrightarrow{GH}}$