4(x+9)=2x-6 Solve for x

Question

4(x+9)=2x-6
Solve for x

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Cherry 5 months 2021-08-15T07:05:30+00:00 2 Answers 4 views 0

Answers ( )

  1. thuthao
    0
    2021-08-15T07:06:39+00:00
    Reply

    Hi there!

    We are given the equation below:

    \large \boxed{4(x + 9) = 2x - 6}

    1. Expand 4 in the expression.

    • When expand in the expression, it is like multiply everything in the expression. So when we expand 4 in x+9, it becomes 4(x)+9(4).

    \large{(4 \times x) + (9 \times 4) = 2x - 6} \\ \large{(4x) + (36) = 2x - 6}

    Cancel the brackets.

    \large{4x + 36 = 2x - 6}

    2. Isolate x–term and solve for the variable.

    • Think it easy. If you want to isolate x-term then what should you do? Well simply swap sides, and change the operator/sign.

    \large{4x - 2x = - 6 - 36}

    Finally, combine like terms.

    \large{2x = - 42}

    Then divide both sides by 2 so we can finally leave only x-term.

    \large{ \frac{2x}{2} = \frac{ - 42}{2} } \\ \large \boxed{x = - 21}

    3. Check the solution if it is right or wrong.

    • This step is optional but if you are not confident on your answer, this step is recommended.

    To check the answer, we simply substitute the value of x which is -21 in the equation and see if both sides are equal or not. If both sides are equal then the answer is correct, if not then the answer is wrong. Therefore,

    \large{4(x + 9) = 2x - 6 \longrightarrow 4( - 21 + 9) = 2 ( - 21) - 6} \\ \large{4( - 12) = - 42 - 6} \\ \large{ - 48 = - 48}

    Since both sides are equal when substitute in x = -21.

    4. Answer

    • Hence, the answer for this equation is x = –21.

    I hope this helps and let me know if you have any doubts!

  2. Sapo1
    1
    2021-08-15T07:07:19+00:00
    Reply

    Answer:

    -21

    Step-by-step explanation:

    4(x+9) = 4x+36

    4x+36 = 2x-6

        -36        -36

    minus 36 from both sides

    4x = 2x-42

    2x = -42

    -42/2 = -21

    x = -21

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Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )