Explanation:
5(2 + 1) can be simplified using the distributive property of multiplication over addition, which states that a(b + c) = ab + ac. Using this property, we get:
5(2 + 1) = 5(2) + 5(1)
Simplifying the expression further, we get:
5(2) + 5(1) = 10 + 5 = 15
Therefore, 5(2 + 1) is equivalent to 15.