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Thread: justification

  1. #1
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    justification

    The steps to solving an equation are shown below. Provide a justification for steps 2, 3, and 4.

    1. 8x 5 = -2x - 15. 1. Given
    2. 10x 5 = -15. 2.
    3. 10x = -10. 3.
    4. x = -1. 4.

  2. #2
    Elite Member mmm4444bot's Avatar
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    What have you thought about so far, in this exercise?

  3. #3
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    2. 10x-5=-15 multiply of equality
    3. 10x=-10 adding of equality
    4. x=-1 divide of equality

  4. #4
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    The steps to solving an equation are shown below. Provide a justification for steps 2, 3, and 4.

    1. 8x 5 = -2x - 15. 1. Given
    2. 10x 5 = -15. 2.
    2. 10x-5=-15 multiply of equality
    Is that your final answer? (meaning: are you sure about that?)

  5. #5
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    Hello, annad95!

    The steps to solving an equation are shown below.
    Provide a justification for steps 2, 3, and 4.

    [tex]\begin{array}{ccccccc}1.& 8x - 5 \:=\: -2x - 15 && 1.& \text{Given } \\
    2. & 10x - 5 \:=\: -15 && 2. & --- \\
    3. & 10x \:=\: -10 && 3. & --- \\
    4. & x \:=\: -1 && 4. & --- \end{array}[/tex]

    Here's my version . . .


    [tex]\begin{array}{ccccccccc}1.& 8x - 5 \:=\: -2x - 15 && 1.& \text{Given } \\
    2. & 10x - 5 \:=\: -15 && 2. & \text{add'n of equality} & \text{(Add }2x\text{ to both sides)} \\
    3. & 10x \:=\: -10 && 3. & \text{add'n of equality} & \text{(Add 5 to both sides)} \\
    4. & x \:=\: -1 && 4. & \text{div'n of equality} & \text{(Divide both sides by 10)} \end{array}[/tex]

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