Algebra


  1. What will be the angle between the lines y – x – 7 = 0 and √3y – x + 6 = 0 ?









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    We know that angle between the lines is

    tanθ =
    m1 + m2
    1 + m1m2

    Here, Equation of line is y – x – 7 = 0
    ⇒ m1 = 1
    similarly,
    m2 =
    1
    3

    Now,

    tanθ = (2 - √3)
    θ = tan–1(2 - √3)

    Correct Option: B

    We know that angle between the lines is

    tanθ =
    m1 + m2
    1 + m1m2

    Here, Equation of line is y – x – 7 = 0
    ⇒ m1 = 1
    similarly,
    m2 =
    1
    3

    Now,

    tanθ = (2 - √3)
    θ = tan–1(2 - √3)


  1. Equation of line 3x + 2y – 5 = 0 can be written in intercept form as









  1. View Hint View Answer Discuss in Forum

    When a line cuts an intercept of a and b x-axis. Its equation will be

    x
    +
    y
    ab

    ⇒ 3x + 2y – 5 = 0
    ⇒ 3x + 2y = 5
    Dividing by 5 on both sides, we get
    3
    x +
    2
    y = 1
    55

    x + y = 1 (Desired Result)
    5
    5
    22

    Correct Option: A

    When a line cuts an intercept of a and b x-axis. Its equation will be

    x
    +
    y
    ab

    ⇒ 3x + 2y – 5 = 0
    ⇒ 3x + 2y = 5
    Dividing by 5 on both sides, we get
    3
    x +
    2
    y = 1
    55

    x + y = 1 (Desired Result)
    5
    5
    22



  1. What is the distance between the parllel lines 15x + 8y – 34 = 0 and 15x + 8y + 31 = 0 ?









  1. View Hint View Answer Discuss in Forum

    Distance between two parallel lines 15x + 8y – 34 = 0 and 15x + 8y + 31 = 0 be d

    ⇒ d =
    15x + 8y - 34
    15² + 8²

    We know that from second equation 15x + 8y = –31
    ⇒ d =
    -31 - 34
    225 + 64

    =
    -65
    289

    =
    -65
    17

    d =
    65
    units
    17

    Correct Option: D

    Distance between two parallel lines 15x + 8y – 34 = 0 and 15x + 8y + 31 = 0 be d

    ⇒ d =
    15x + 8y - 34
    15² + 8²

    We know that from second equation 15x + 8y = –31
    ⇒ d =
    -31 - 34
    225 + 64

    =
    -65
    289

    =
    -65
    17

    d =
    65
    units
    17


  1. Find the ratio in which the line segment joining the points (1, 2) and (4, 6) is divided by point (2, 0).









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    Let the ratio be k : 1

    Using internal section formula

    2 =
    4 × k + 1 × 1
    k + 1

    ⇒ 2(k + 1) = 4k + 1
    2k + 2 = 4k + 1
    –2k = –1
    k =
    1
    2

    and
    0 =
    6 × k + 1 × 2
    k + 1

    0 (k + 1) = 6k + 2
    6k = –2
    k =
    - 1
    3

    The value of k is not negative.
    ∴ Ratio will be 1 : 2

    Correct Option: A

    Let the ratio be k : 1

    Using internal section formula

    2 =
    4 × k + 1 × 1
    k + 1

    ⇒ 2(k + 1) = 4k + 1
    2k + 2 = 4k + 1
    –2k = –1
    k =
    1
    2

    and
    0 =
    6 × k + 1 × 2
    k + 1

    0 (k + 1) = 6k + 2
    6k = –2
    k =
    - 1
    3

    The value of k is not negative.
    ∴ Ratio will be 1 : 2



  1. What is the distance of the point (2, 3) from the line 2x + 3y + 4 = 0 ?









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    Let the distance be d

    ⇒ d =
    2x + 3y + 4
    2² + 3²

    d(2,3) =
    2 × 2 + 3 × 3 + 4
    13

    d(2,3) =
    17
    units
    13

    ⇒ d(2,3) =
    17
    units
    13

    Correct Option: C

    Let the distance be d

    ⇒ d =
    2x + 3y + 4
    2² + 3²

    d(2,3) =
    2 × 2 + 3 × 3 + 4
    13

    d(2,3) =
    17
    units
    13

    ⇒ d(2,3) =
    17
    units
    13