Which expressions are equivalent to -9 (2/3x + 1) Check the two that apply.

(2 points)
• -6x - 9
-9 (2/3x) - 9(1)
* -6x + 9
* -9 (2/3x) + 9 (1)
* -6x + 1

1 answer

To determine which expressions are equivalent to \(-9 \left( \frac{2}{3}x + 1 \right)\), we'll first simplify this expression.

  1. Distribute \(-9\):

\[ -9 \left( \frac{2}{3}x + 1 \right) = -9 \cdot \frac{2}{3}x - 9 \cdot 1 \]

  1. Calculate \(-9 \cdot \frac{2}{3}x\):

\[ -9 \cdot \frac{2}{3} = -6 \] So this part becomes \(-6x\).

  1. Now subtract \(9\):

\[ -6x - 9 \]

Thus, the original expression simplifies to:

\[ -6x - 9 \]

Now let's compare this with each of the given options to find which ones are equivalent to \(-9 \left( \frac{2}{3}x + 1 \right)\):

  1. -6x - 9 (This is equivalent, as shown.)
  2. -9 (2/3x) - 9(1) (This is equivalent as it expands to \(-6x - 9\).)
  3. -6x + 9 (Not equivalent, since this would equal \(-6x\) plus a positive \(9\).)
  4. -9 (2/3x) + 9 (1) (This simplifies to \(-6x + 9\), not equivalent.)
  5. -6x + 1 (Not equivalent, as it does not match.)

So, the two expressions that are equivalent to \(-9 \left( \frac{2}{3}x + 1 \right)\) are:

  • \(-6x - 9\)
  • \(-9 (2/3x) - 9(1)\)

Therefore the correct selections are:

  • -6x - 9
  • -9 (2/3x) - 9(1)