Question

find the missing number so that the equation has no solutions. \\(\square x + 15 = 4(x + 2)\\)

Explanation:

Step1: Expand right-hand side

$4(x+2) = 4x + 8$

Step2: Set coefficient of $x$ equal

Let the missing number be $a$. For no solutions, $a=4$ (so $x$ terms cancel, leaving a false statement).

Step3: Verify the constant terms

With $a=4$, equation becomes $4x+15=4x+8$. Subtract $4x$: $15=8$, which is false.

Answer:

4