Answer: B. $15x+150$

Explanation:1. Use the distributive property: The distributive property states that $a(b+c) = ab + ac$. In this case, $a=15$, $b=x$, and $c=10$.

2. Apply the property to the given expression: $15(x+10) = 15 \times x + 15 \times 10$

3. Perform the multiplications: $15 \times x = 15x$ $15 \times 10 = 150$

4. Combine the terms: $15(x+10) = 15x + 150$

5. Check the options: Option [B] is $15x+150$, which matches our result.

6. Conclusion: The expression equivalent to $15(x+10)$ is $15x+150$. Option [B] is correct.