Solve 5(x - 2) = 3x + 10.

• A. 0
• B. 10
• C. -10
• D. 5

Answer: (B)

Solving a linear equation like this relies on distributing any factors and then collecting like terms to isolate x. Start by applying the distributive property to 5(x − 2): that gives 5x − 10 on the left, so the equation becomes 5x − 10 = 3x + 10. Next move the x terms to one side by subtracting 3x from both sides, yielding 2x − 10 = 10. Then move the constant term to the other side by adding 10 to both sides, which gives 2x = 20. Finally divide by 2 to isolate x, so x = 10. You can check by substituting back: 5(10 − 2) = 40 and 3·10 + 10 = 40, which match. The value 10 is the solution because it satisfies the equation.