Parallel and Intersecting Lines — Quiz

Q1. Two adjacent angles formed by two intersecting straight lines are called a

• A. Linear pair.
• B. Vertically opposite pair.
• C. Pair of corresponding angles.
• D. Pair of alternate angles.

Q2. In Fig. 5.2, lines l and m intersect at a point forming angles a, b, c, d. If ∠a = 120°, what is the measure of the vertically opposite angle ∠c?

• A. 60°
• B. 90°
• C. 120°
• D. 240°

Q3. In Fig. 5.3, two lines intersect forming angles a, b, c, d going around the point. How many distinct linear pairs are formed in this figure?

• A. Two
• B. Three
• C. Four
• D. Six

Q4. On a figure, perpendicular lines are commonly indicated by drawing which mark at the point where they meet?

• A. A small arrow on each line.
• B. A small circle around the intersection.
• C. A short dash on each line.
• D. A small square at the corner.

Q5. Two straight lines that never meet but lie on two different planes (for example, a line on the floor and a line on the wall not facing each other) are

• A. Parallel lines.
• B. Intersecting lines.
• C. Perpendicular lines.
• D. Not called parallel — the same-plane condition is missing.

Q6. Which of these everyday objects is an example of parallel lines as discussed in the chapter?

• A. The two hands of a clock at 3 o'clock.
• B. Two pencils placed in a 'plus' shape.
• C. Two diagonals of a square sheet of paper.
• D. The opposite long rails of a railway track.

Q7. Priya takes a rectangular sheet of paper. The two opposite long edges of the sheet are best described as

• A. Parallel to each other.
• B. Perpendicular to each other.
• C. Intersecting at a midpoint.
• D. Forming a linear pair.

Q8. Ravi takes a square sheet of paper and folds it horizontally once. Counting the new fold line together with the two original horizontal edges, how many parallel lines does he see?

• A. Two
• B. Five
• C. Four
• D. Three

Q9. When a transversal crosses two lines, eight angles are formed. The maximum number of distinct (different) angle measures possible among these eight angles is

• A. Two
• B. Eight
• C. Six
• D. Four

Q10. When a transversal t intersects two lines l and m as in Fig. 5.14, the total number of pairs of corresponding angles formed is

• A. Two
• B. Three
• C. Four
• D. Eight

Q11. A transversal t cuts two lines l and m. A pair of corresponding angles formed is found to be equal. From this we can conclude

• A. Lines l and m are perpendicular to t.
• B. Nothing — corresponding angles can be equal by accident.
• C. Lines l and m must coincide.
• D. Lines l and m are parallel to each other.

Q12. A transversal cuts a pair of lines that are NOT parallel to each other. About the corresponding angles formed, we can say

• A. They are still equal.
• B. They are all right angles.
• C. They add up to 180°.
• D. They can never be equal to each other.

Q13. In Fig. 5.25, lines l and m are parallel and t is a transversal. ∠d and ∠f are alternate angles. If ∠f = 120°, then ∠d equals

• A. 60°
• B. 90°
• C. 120°
• D. 180°

Q14. When a transversal intersects a pair of parallel lines, the interior angles on the same side of the transversal (co-interior angles) always add up to

• A. 90°
• B. 120°
• C. 180°
• D. 360°

Q15. In Fig. 5.28, parallel lines l and m are cut by transversal t. ∠3 and ∠6 are interior angles on the same side. If ∠3 = 50°, the measure of ∠6 is

• A. 50°
• B. 100°
• C. 130°
• D. 180°