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Thread: Algebraic Proof

  1. #1
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    Algebraic Proof

    Use the statement vs reason chart to show that
    5x - 4 = 6 has a solution of x = 2.
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  2. #2
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    Re: Algebraic Proof

    are you really saying you can't figure out how to solve

    $5x-4=6$
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  3. #3
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    Re: Algebraic Proof

    You are still posting problems with no indication that you have made any attempt to do it your self! That makes it very difficult to know what you can do, where you have a problem, or what hints would help.

    Do you know what "statement vs reason chart" means?

    If you were asked to solve the equation algebraically, could you do it?

    If so, give each step as a "statement" and why each works as a "reason".

    For example, the first thing I would do is add four to both sides. The "statement" would be "add 4 to both sides of the equation". The "reason" is that "equals added to equals are equal". That leaves 5x= 10. What should you do now? How do you know you can do it?
    Last edited by HallsofIvy; Feb 5th 2017 at 12:20 PM.
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    Re: Algebraic Proof

    Quote Originally Posted by romsek View Post
    are you really saying you can't figure out how to solve

    $5x-4=6$
    No. I am not saying the linear equation is too hard for me.
    I want to learn how to prove that x = 2 makes the original equation a true statement using the statements vs reasons chart.
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  5. #5
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    Re: Algebraic Proof

    Quote Originally Posted by HallsofIvy View Post
    You are still posting problems with no indication that you have made any attempt to do it your self! That makes it very difficult to know what you can do, where you have a problem, or what hints would help.

    Do you know what "statement vs reason chart" means?

    If you were asked to solve the equation algebraically, could you do it?

    If so, give each step as a "statement" and why each works as a "reason".

    For example, the first thing I would do is add four to both sides. The "statement" would be "add 4 to both sides of the equation". The "reason" is that "equals added to equals are equal". That leaves 5x= 10. What should you do now? How do you know you can do it?
    I will show my work later tonight.
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  6. #6
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    Re: Algebraic Proof

    Quote Originally Posted by romsek View Post
    are you really saying you can't figure out how to solve

    $5x-4=6$
    $5x - 4 = 6$

    $\begin{array}{ll}

    \text{Statement} &\text{Reason} \\

    \hline &\hline \\

    5x -4 + 4= 6+4 &\text{Add 4 to both sides} \\

    5x = 10 &\text{Addition} \\

    \dfrac{5x}{5} = \dfrac{10}{5} &\text{Divide both sides by 5} \\

    x = 2 &\text{Division}

    \end{array}$
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  7. #7
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    Re: Algebraic Proof

    Quote Originally Posted by romsek View Post
    $5x - 4 = 6$

    $\begin{array}{ll}

    \text{Statement} &\text{Reason} \\

    \hline &\hline \\

    5x -4 + 4= 6+4 &\text{Add 4 to both sides} \\

    5x = 10 &\text{Addition} \\

    \dfrac{5x}{5} = \dfrac{10}{5} &\text{Divide both sides by 5} \\

    x = 2 &\text{Division}

    \end{array}$
    I will list the statements first.

    Statements

    1. 5x - 4 = 6

    2. 5x = 6 + 4

    3. 5x/5 = 10/5

    4. x = 2

    Reasons

    1. Given

    2. Addition property of equality

    3. Division property of equality

    4. Proved by statement 3.

    How about this chart?
    Last edited by mathdad1965; Feb 5th 2017 at 09:07 PM.
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  8. #8
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    Re: Algebraic Proof

    even better
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  9. #9
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    Re: Algebraic Proof

    Quote Originally Posted by romsek View Post
    even better
    Great!
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