Question

    Find the equation of the line passing through the points

    (1, 2) and (3, 8).
    A y = 3x - 1 Correct Answer Incorrect Answer
    B y = 3x + 1 Correct Answer Incorrect Answer
    C y = 4x - 2 Correct Answer Incorrect Answer
    D y = 4x - 1 Correct Answer Incorrect Answer

    Solution

    The formula for the slope of a line through two points (x1, y1) and (x2, y2) is: Slope m = (y2 - y1) / (x2 - x1). Substituting the given points (1, 2) and (3, 8): m = (8 - 2) / (3 - 1) = 6 / 2 = 3. Now, using the point-slope form of the line equation: y - y1 = m(x - x1). Substitute m = 3 and point (1, 2): y - 2 = 3(x - 1), y - 2 = 3x - 3, y = 3x - 1. Answer: a) y = 3x - 1.

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