Respuesta :

mewtoreks

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

VectorFundament120

Hi there!

We are given the equation below:

[tex] \large \boxed{4(x + 9) = 2x - 6}[/tex]

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).

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

Cancel the brackets.

[tex] \large{4x + 36 = 2x - 6}[/tex]

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.

[tex] \large{4x - 2x = - 6 - 36}[/tex]

Finally, combine like terms.

[tex] \large{2x = - 42}[/tex]

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

[tex] \large{ \frac{2x}{2} = \frac{ - 42}{2} } \\ \large \boxed{x = - 21}[/tex]

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,

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

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!

Otras preguntas