Which set notation correctly expresses the solution set to the equation 31-9x=4

A. {3}

B. (3)

C. {x=3}

D. (x=3)

1 answer

To solve the equation \( 31 - 9x = 4 \):

  1. Subtract 31 from both sides: \[ -9x = 4 - 31 \] \[ -9x = -27 \]

  2. Divide by -9: \[ x = \frac{-27}{-9} = 3 \]

The solution to the equation is \( x = 3 \).

Now let's analyze the answer choices given in terms of set notation:

A. {3} - This correctly represents the solution as a set containing the number 3.

B. (3) - This is not a standard notation for expressing a solution set.

C. {x=3} - This is also not standard; it represents a set containing the statement \( x = 3 \), not the solution itself.

D. (x=3) - This is not a correct representation of a solution set.

The correct answer, expressing the solution set in proper set notation, is:

A. {3}