31:T463,

Tangent Line

A line that touches a curve at a point without crossing over. Formally, it is a line which intersects a differentiable curve at a point where the slope of the curve equals the slope of the line.

Note: A line tangent to a circle is perpendicular to the radius to the point of tangency.

An S-shaped curve on an x-y coordinate plane with a straight tangent line touching the curve at one point, labeled "tangent line.

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