GeometryBASIC CONCEPTS OF GEOMETRYIf angles are next to each other, they are called adjacent angles. If the sum of two angles equals90°, they are called complimentary angles. For example, 27° and 63° are complimentary angles.If the sum of two angles equals 180°, they are called supplementary angles. For example, 73°and 107° are supplementary angles.SummaryThe important information in this chapter is summarized below.Lines and Angles SummaryStraight lines are parallel when they are in the same plane and donot intersect.A straight angle is 180°.An acute angle is less than 90°.A right angle is 90°.An obtuse angle is greater than 90° but less than 180°.If the sum of two angles equals 90°, they are complimentaryangles.If the sum of two angles equals 180°, they are supplementaryangles.Rev. 0 Page 5 MA-03

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