Straight Angle Small 320×43 Medium 640×86 Large 1024×137 Download Tiff Original 2400×321 | (63.8 KB) Description An illustration showing a straight angle. When the sides of an angle extend in opposite directions, so as to be in the same straight line, the angle is called a straight angle. Keywords angle, angles, geometry, line, lines, same vertex, straight Galleries Miscellaneous Angles Source: G.A. Wentworth Plane And Solid Geometry (Boston: Ginn & Company, 1899) 11 Courtesy the private collection of Roy Winkelman