Scalene (all sides diff)

Isoceles (2 sides are equal)

Equalateral(all sides are equal)

Sum of the interior angles of traingle =180degree

Angle BOC=90+1/2 angle A

Ext. angle +Sum of 2 interior opp. angles

Right =90 degree

Acute=0<90degree

Obtuse (90degree<0<180degree

1. Corresponding angles = angle-2,5;2,6;3,7;4,8

Alternate interior angles=angle 1,7;2,8

Co-interior angles=angle1+angle8=180degree=angle2+angle7