To represent the situation, we start with the information that Mark has 2 candles and needs at least 7 candles in total for the birthday party.
Let \( x \) represent the number of candles he buys. The total number of candles he will have after buying \( x \) candles is \( x + 2 \).
Since he needs at least 7 candles:
\[ x + 2 \geq 7 \]
We can subtract 2 from both sides to isolate \( x \):
\[ x \geq 5 \]
So the correct inequality that represents the number of candles he could buy is:
x + 2 ≥ 7
Thus, the correct answer is:
x + 2 ≥ 7 (x plus 2 is greater than or equal to 7).