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    • Thread Starter

    How the heck do I do this

    This is a simultaneous equation
    Firstly, the way I do it is by eliminating the x first

    To do this, you have to make the y values for both equations the same. In this instance, you can multiply the top one by 6 to make it 6y (same as bottom)
    Note you have to multiply all values in the equation you are multiplying.

    Therefore, you'd get
    30a + 6y = 90
    2a + 6y = 34

    Theres a rule of if its the same sign, we subtract, and as we can see there are two addition signs in the equation.
    So we get:
    28a = 56 (bcos 30-2 = 28 and 90-34 = 56)
    so a = 2

    To get y we just input the a value to the first set of equations we started with.
    so 5a + y = 15
    5 x 2 + y = 15
    10 + y = 15
    y must be 5

    (can check with bottom equation it is correct)

    a is 2 and y is 5.

    Posted from TSR Mobile
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