Write an equation in factored form given the “a” value is -3 and the x-intercepts are -2 and 5. (Hint: write your equation with no spaces. W

Question

Write an equation in factored form given the “a” value is -3 and the x-intercepts are -2 and 5. (Hint: write your equation with no spaces. Write the term with “2” first)

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Eden 1 day 2021-09-10T04:35:15+00:00 1 Answer 0

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    2021-09-10T04:37:07+00:00

    Answer:

    -3(x-5)(x+2)

    Step-by-step explanation:

    the generic form of a second degree equation is:

    y = ax^2 + bx + c

    with “a” = -3, we have y = -3x^2 + bx + c

    for y=0 (x-intercepts), we have x = -2 and x = 5, so:

    1: 0 = -3*(-2)^2 + b*(-2) + c

    -12 -2b + c = 0

    -2b + c = 12 (eq1)

    2: 0 = -3*5^2 + b*5 + c

    -75 + 5b + c = 0

    5b + c = 75 (eq2)

    doing (eq2) – (eq1), we have:

    7b = 63 -> b = 9

    using b = 9 in (eq1), we have:

    -18 + c = 12 -> c = 30

    so, the equation is y = -3×2 + 9x + 30

    in factored form: y = -3(x2 – 3x – 10) = -3(x-5)(x+2)

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45:7+7-4:2-5:5*4+35:2 =? ( )