Answer:
![x^(2) + 10x + 25](https://img.qammunity.org/2020/formulas/mathematics/high-school/13ytitjyqfeqp6rn3esiull0vnz0o4h8eo.png)
Explanation:
Let's first re-write the problem expression.
![(x +5)^(2) = (x+5) (x+5)](https://img.qammunity.org/2020/formulas/mathematics/high-school/wpi6qd1ijlluuotmwud2z91tq5jh3t56bx.png)
Then we apply the distributive property to get
(x + 5)(x+5) = x(x+5) + 5(x+5)
We broke up the first (x+5) to use the x and the 5 to multiply the second (x+5) element... then add them to each other (because of the + sign).
![x(x+5) + 5(x+5) = (x^(2) + 5x) + (5x + 25) = x^(2) + 10x + 25](https://img.qammunity.org/2020/formulas/mathematics/high-school/t6x5y3kgpfvofcjswljy7e7uj04d6egpfr.png)