4. What type of angles are formed when two lines intersect and share a common 5. In a linear pair, the angles add up to: 6. What is the measure of the supplementary angle of a \( 70^{\circ} \) angle? 7. Convex or Concave: All of its interior angles are less than \( 180^{\circ} \) 8. Convex or Concave: It has at least one interior angle greater than \( 180^{\circ} \)

4. When two lines intersect and share a common point, they form four angles. These angles are called vertical angles. Vertical angles are always equal in measure. 5. In a linear pair, the angles are adjacent and form a straight line. The sum of the measures of the angles in a linear pair is always \( 180^{\circ} \). 6. The supplementary angle of an angle is the angle that, when added to the original angle, equals \( 180^{\circ} \). To find the measure of the supplementary angle of a \( 70^{\circ} \) angle, you would subtract \( 70^{\circ} \) from \( 180^{\circ} \): \[ 180^{\circ} - 70^{\circ} = 110^{\circ} \] So, the measure of the supplementary angle of a \( 70^{\circ} \) angle is \( 110^{\circ} \). 7. A polygon is convex if all of its interior angles are less than \( 180^{\circ} \). Therefore, the statement "All of its interior angles are less than \( 180^{\circ} \)" describes a convex polygon. 8. A polygon is concave if it has at least one interior angle greater than \( 180^{\circ} \). Therefore, the statement "It has at least one interior angle greater than \( 180^{\circ} \)" describes a concave polygon.