alternate angles

American  

plural noun

Geometry.

1. two nonadjacent angles made by the crossing of two lines by a third line, both angles being either interior or exterior, and being on opposite sides of the third line.

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alternate angles British  

plural noun

1. two angles at opposite ends and on opposite sides of a transversal cutting two lines

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alternate angles Scientific  

1. Two angles formed on opposite sides of a line that crosses two other lines. The angles are both exterior or both interior, but not adjacent.

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Etymology

Origin of alternate angles

First recorded in 1650–60

Example Sentences

Two cameramen crouch in front, capturing him from alternate angles — one locked on his made-for-TV visage and the other set to pan across his body once he starts delivering his lines.

From Los Angeles Times • Aug. 28, 2022

DW: You could see in some of those alternate angles how clear of an angle Crowder had to see the rim.

From Los Angeles Times • Jun. 24, 2021

Six holes play right on the shoreline, and every hole offer genuine alternate angles of attack.

From Golf Digest • Jan. 11, 2018

The fort was inclosed by high pickets, with bastions at the alternate angles.

From Wau-bun The Early Day in the Northwest by Kinzie, Juliette Augusta Magill

Hence we know that, “if two straight lines which are cut by a transversal meet, their alternate angles are not equal”; and hence that, “if alternate angles are equal, then the lines are parallel.”

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various