An exterior angle is outside the triangle and next to one of the sides. 4-2 Exterior Angle Theorem.

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An exterior angle is outside the triangle and next to one of the sides. 4-2 Exterior Angle Theorem

Remote interior angle: an interior angle that is not adjacent to (not touching, away from) an exterior angle. There are always 2 remote interior angles for each exterior angle. *If you add the remote interior angles, they equal the exterior angle Interior Exterior m1 + m2 = m4

Examples 1) 2) 120° x x + 90 = 120 x = 30 2x = 5x x + 18 = 5x – = 3x – = 3x 26 = x

Solve for the value of x x + 2 = 8 + 6x 4x + 32 = 8 + 6x 32 = 8 + 2x 24 = 2x 12 = x