LINES AND ANGLESTYPES OF TRIANGLEBASIS OF SIDESPROPERTIESSum of the interior angles of traingle =180degree Angle BOC=90+1/2 angle AExt. angle +Sum of 2 interior opp. anglesAngle BOC=90-1/2BASIS OF ANGLESRight =90 degreeAcute=0<90degreeObtuse (90degree<0<180degreeScalene (all sides diff)Isoceles (2 sides are equal)Equalateral(all sides are equal)Angles made by transeval1. Corresponding angles = angle-2,5;2,6;3,7;4,8Alternate interior angles=angle 1,7;2,8Co-interior angles=angle1+angle8=180degree=angle2+angle7Alternate exterior angle angle4,angle6;;angle3,angle5TYPES OF ANGLESPAIR OF ANGLESZero AngleAcute AngleRelex AngleRight AngleGreater than 0° but less than 90°Equal to 90°Obtuse AngleMore than 90° but less than 180°Straight AngleEqual to 180°More than 180° but less than 360°Complete AngleEqual to 360°Adjacent anglesComplementary anglesSupplementary anglesTwo angles with a common vertex, sharing a common side and no overlap.Two angles, the sum of whose measures is 90°.Two angles, the sum of whose measures is 180°.