## Introductory Algebra for College Students (7th Edition)

$$x = 4$$ 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.
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.