Let's solve the equation step by step:
Given equation: \[ 3x + 18 = 5x + 8 \]
Step 1: Get all terms involving \( x \) on one side of the equation and the constant terms on the other side.
Subtract \( 3x \) from both sides: \[ 18 = 5x - 3x + 8 \]
This simplifies to: \[ 18 = 2x + 8 \]
Step 2: Now, subtract 8 from both sides: \[ 18 - 8 = 2x \] \[ 10 = 2x \]
Step 3: Divide both sides by 2 to isolate \( x \): \[ x = \frac{10}{2} \] \[ x = 5 \]
Conclusion: The solution to the equation is \( x = 5 \).
Since we have found a specific value for \( x \) that satisfies the equation, there is only one solution.
Thus, the answer to how many solutions this equation has is: one (circle and mark "one").