Answer:
x² + 10x + 25
Explanation:
Given
(x + 5)(x + 5)
Each term in the second factor is multiplied by each term in the first factor, that is
x(x + 5) + 5(x + 5) ← distribute both parenthesis
= x² + 5x + 5x + 25 ← collect like terms
= x² + 10x + 25 ← in standard form