#### Answer

$$x = 4$$
To check if the solution is correct, substitute $4$ for $x$ to see if both sides of the equation are equal:
$$5(4) + 16 = 3(4 + 8)$$
Evaluate what is in parentheses first:
$$5(4) + 16 = 3(12)$$
Multiply on both sides of the equation:
$$20 + 16 = 36$$
Add terms on left-hand side of the equation:
$$36 = 36$$
Both sides of the equation are equal, so the solution is correct.

#### Work Step by Step

We solve the equation by isolating the variable on one side and constants on the other.
First, distribute what is in parentheses:
$$5x + 16 = 3x + 24$$
Subtract $3x$ from both sides to move the variable to one side of the equation:
$$2x + 16 = 24$$
Subtract $16$ from both sides to isolate the constants on one side of the equation:
$$2x = 8$$
Divide by $2$ to solve for $x$:
$$x = 4$$
To check if the solution is correct, substitute $4$ for $x$ to see if both sides of the equation are equal:
$$5(4) + 16 = 3(4 + 8)$$
Evaluate what is in parentheses first:
$$5(4) + 16 = 3(12)$$
Multiply on both sides of the equation:
$$20 + 16 = 36$$
Add terms on the left-hand side of the equation:
$$36 = 36$$
Both sides of the equation are equal, so the solution is correct.