Chapter-9 Straight Lines — Online MCQ Test
MATHS · Grade 11 · CBSE(NCERT)
Practice Chapter-9 Straight Lines with a free chapter-wise online MCQ test.
This chapter covers: Slope of a line - Collinearity - Angle between two lines - Point-slope form - Slope-intercept form - Two-point form - Intercept form - General equation - Distance of a point from a....
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter-9 Straight Lines — Important Questions & Answers
What is the slope of a line passing through points (2, 3) and (5, 9)?
- A. 2
- B. 3
- C. 1
- D. 4
Answer: A. 2
Slope m = (y₂ - y₁)/(x₂ - x₁) = (9 - 3)/(5 - 2) = 6/3 = 2.
Slope m = (y₂ - y₁)/(x₂ - x₁) = (9 - 3)/(5 - 2) = 6/3 = 2.
What is the y-intercept of the line 3x + 2y = 6?
- A. 2
- B. 3
- C. 6
- D. 1
Answer: B. 3
Setting x = 0: 2y = 6, so y = 3. The y-intercept is 3.
Setting x = 0: 2y = 6, so y = 3. The y-intercept is 3.
Find the equation of a line passing through (2, 3) with slope 2 using point-slope form.
- A. y - 3 = 2(x - 2)
- B. y + 3 = 2(x + 2)
- C. y - 2 = 3(x - 3)
- D. 2y - 3 = x
Answer: A. y - 3 = 2(x - 2)
Using point-slope form: y - y₁ = m(x - x₁), we get y - 3 = 2(x - 2).
Using point-slope form: y - y₁ = m(x - x₁), we get y - 3 = 2(x - 2).
The line passing through (2, 3) perpendicular to the line 4x + 3y = 7 has slope:
- A. 3/4
- B. -3/4
- C. 4/3
- D. -4/3
Answer: A. 3/4
Slope of 4x + 3y = 7 is -4/3. Perpendicular slope = -1/(-4/3) = 3/4.
Slope of 4x + 3y = 7 is -4/3. Perpendicular slope = -1/(-4/3) = 3/4.
Three points P(h, 0), Q(0, k), and R(1, 1) are collinear. Which relation must hold?
- A. h + k = hk
- B. 1/h + 1/k = 1
- C. h - k = 0
- D. hk = 1
Answer: B. 1/h + 1/k = 1
For collinearity, slope PQ = slope QR. This gives: -k/h = (1 - k)/(1 - 0). Solving: -k(1) = h(1 - k) → -k = h - hk → h + k = hk. Rearranging: 1/h + 1/k = 1.
For collinearity, slope PQ = slope QR. This gives: -k/h = (1 - k)/(1 - 0). Solving: -k(1) = h(1 - k) → -k = h - hk → h + k = hk. Rearranging: 1/h + 1/k = 1.