Remmi wrote the equation of the line [tex]y=\frac{1}{3}(x+2)[/tex]. He solved for [tex]x[/tex] and got [tex]x=3y-2[/tex]. Which of the following is an equivalent equation for [tex]x[/tex]?

A. [tex]x=y-\frac{11}{3}[/tex]
B. [tex]x=y+\frac{7}{3}[/tex]
C. [tex]x=3\left(y-\frac{2}{3}\right)[/tex]
D. [tex]x=3\left(y+\frac{2}{3}\right)[/tex]



Answer :

To solve this problem, we need to determine which of the given options is equivalent to the equation [tex]\( x = 3y - 2 \)[/tex].

Let's start with each option:

1. [tex]\( x = y - \frac{11}{3} \)[/tex]
2. [tex]\( x = y + \frac{7}{3} \)[/tex]
3. [tex]\( x = 3\left(y - \frac{2}{3}\right) \)[/tex]
4. [tex]\( x = 3\left(y + \frac{2}{3}\right) \)[/tex]

Let's explore option 3 first:

Option 3: [tex]\( x = 3\left(y - \frac{2}{3}\right) \)[/tex]

We can distribute the 3 inside the parentheses to simplify the equation:
[tex]\[ x = 3 \cdot y - 3 \cdot \frac{2}{3} \][/tex]
[tex]\[ x = 3y - 2 \][/tex]

As we see, this simplifies to [tex]\( x = 3y - 2 \)[/tex], which matches the equation derived from solving for [tex]\( x \)[/tex].

Next, let's check the other options to be thorough:

Option 1: [tex]\( x = y - \frac{11}{3} \)[/tex]

There’s no way to manipulate [tex]\( x = y - \frac{11}{3} \)[/tex] to become [tex]\( x = 3y - 2 \)[/tex], as this option does not correctly scale or match the coefficient for [tex]\( y \)[/tex].

Option 2: [tex]\( x = y + \frac{7}{3} \)[/tex]

Similarly, [tex]\( x = y + \frac{7}{3} \)[/tex] cannot be adjusted to match [tex]\( x = 3y - 2 \)[/tex].

Option 4: [tex]\( x = 3\left(y + \frac{2}{3}\right) \)[/tex]

Distributing the 3 inside the parentheses results in:
[tex]\[ x = 3 \cdot y + 3 \cdot \frac{2}{3} \][/tex]
[tex]\[ x = 3y + 2 \][/tex]

This does not match the target equation [tex]\( x = 3y - 2 \)[/tex].

Therefore, the correct equivalent equation for [tex]\( x \)[/tex] derived from the original equation [tex]\( y = \frac{1}{3}(x+2) \)[/tex] is:

[tex]\[ x = 3\left(y - \frac{2}{3}\right) \][/tex]

So the correct answer is:
[tex]\[ \boxed{x = 3\left(y - \frac{2}{3}\right)} \][/tex]