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Math-Algebra

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Solve: 3x-2y=10 2x+3y=-2

Graph:
Substitution:
Elimination:

Show Your work!
(I can'tfigure out how to graph it and when i used substitution and elimination it came out with two different anwsers. I need help! and i need to be able to show my work!)

  • Math-Algebra -

    Eq1: 3X - 2Y = 10.
    Eq2: 2X + 3Y = -2.

    Substitution Method:

    In Eq2, solve for X:
    Eq2: 2X + 3Y = -2,
    2X = -3Y - 2,
    X = -3Y/2 - 1,

    In Eq1, substitute -3Y/2 - 1 for X:
    3(-3X/2 - 1) - 2Y = 10,
    -9X/2 - 3 - 2Y = 10,
    Multiply both sides by 2 and get:
    -9X - 6 -4Y = 20,
    -13Y = 20 + 6,
    -13Y = 26,
    Y = 26 / -13 = - 2.

    In Eq2, substitute -2 for Y:
    2X + 3*-2 = -2,
    2X - 6 = - 2,
    2X = -2 + 6,
    2X = 4,
    X = 4 / 2 = 2.

    Solution Set = (2, -2).

    Elimination Method:

    Multiply Eq1 by -2 and Eq2 by 3 and get:

    -6X + 4Y = -20,
    +6X + 9Y = -6
    Add the 2 Eqs and get:
    13Y = -26,
    Y = -26 / 13 = -2.

    Substitute -2 for Y in Eq1:
    3X - 2*-2 = 10,
    3X + 4 = 10,
    3X = 10 - 4,
    3X = 6,
    X = 6 / 3 = 2.

    Solution Set = (2, -2).

    GRAPH: Use the following points.

    Eq1:(-2, -8) (0, -5), (2, -2).

    Eq2: (-2.5, 1),(-4, 2) (2, -2).

    The point where the lines intersect is the solution.

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