214k views
1 vote
If 2x + 5 = 8x, then 12x = ?A.5B.10C.15D.20

1 Answer

5 votes

Answer:


10.\text{ Option B is correct}

Step-by-step explanation:

Given the equation expressed as:


2x+5=8x

First, we need to calculate the value of "x" from the given expression.

Step 1: Given the equation 2x + 5 = 8x

Step 2: Subtract 5 from both sides:


\begin{gathered} 2x+5-5=8x-5 \\ 2x+\cancel{5}-\cancel{5}=8x-5 \\ 2x=8x-5 \end{gathered}

Step 3: Subtract 8x from both sides


\begin{gathered} 2x-8x=8x-8x-5 \\ -6x=\cancel{8x}-\cancel{8x}-5 \\ -6x=-5 \end{gathered}

Step 4: Divide both sides by -6


\begin{gathered} (-6x)/(-6)=(-5)/(-6) \\ x=(5)/(6) \end{gathered}

Step 5: Get the value of 12x. Substitute x = 5/6 into the expression to have:


\begin{gathered} 12x=12((5)/(6)) \\ 12x=\cancel{12}^2(\frac{5}{\cancel{6}^1}) \\ 12x=2*5 \\ 12x=10 \end{gathered}

Therefore the value of 12x is 10

User Brett McCann
by
7.5k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories