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Feilx 發問時間: 科學數學 · 7 年前

F.1 to F.2 math (hard)

Given two points P(a,3) and Q(-5,b), and PQ is a vertical line.

a) Find the value of a.

b)if the distance between PQ is 5 units, find two possible values of b.

1 個解答

評分
  • 7 年前
    最佳解答

    Question

    Given two points P(a, 3) and Q(-5, b),and PQ is a vertical line.

    (a) Find the value of a.

    (b) If the distance between PQ is 5 units, find two possible values of b.

    Solution

    (a)

    A vertical line passes through points which have a common x-coordinate.

    P and Q are on the same vertical line.

    Therefore, a = -5.

    (b)

    PQ is a vertical line, so either Q is above P or Q is below P.

    If Q is above P, then b - 3 = 5, that is b = 8.

    If Q is below P, then 3 - b = 5, that is b = -2.

    Thus, the two possible values of b are 8 and -2.

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