An angle is 80° less than three times its supplement. The angle is

1. 75°
2. 85°
3. 105°
4. 115°

The value of x in the given figure is

1. 24°
2. 28°
3. 36°
4. 42°

Fill in the blanks :

(i) An angle whose measure is more than 180° but less than 360° is called a …………… .

(ii) A straight line that intersects two or more lines in a plane is called a …………… .

(iii) A pair of adjacent angles is said to be a …………… if these angles have one arm common and other arms as opposite rays.

(iv) Two intersecting lines make …………… pairs of vertically opposite angles.

(v) Two lines are said to be …………… to each other if they intersect at right angles.

Write true (T) or false (F) :

(i) An angle whose measure is 90° is called a straight angle.

(ii) The sum of the angles of a linear pair is 180°.

(iii) When two straight lines cut each other, the sum of any two adjacent angles formed is 180°.

(iv) A line which intersects two other lines at their point of intersection is called a transversal.

(v) When two parallel lines are cut by a transversal, then the exterior opposite angles are supplementary.