Answer:The correct answer is C. x = 13.
Step-by-step explanation:To solve the equation x + 15 = 28, we want to isolate the variable x on one side of the equation.
To do this, we can subtract 15 from both sides of the equation, since subtracting the same value from both sides maintains the equality.
So, let's subtract 15 from both sides:
x + 15 - 15 = 28 - 15
This simplifies to:
x = 13
Therefore, the solution to the equation x + 15 = 28 is x = 13.