Hi there!
Answer:
p=400
*The answer must have a positive sign.*
Explanation:
Lesson: Using Properties to Simplify Expressions
Distributive property: →→→

First, you multiply by 10 from both sides of an equation.

Then, you refine. You can also multiply by the numbers from left to right.

Next, you divide by 8 from both sides of an equation.

Finally, you simplify and solve. Divide by the numbers from left to right.

Final answer is p=400
I hope this helps you!
Have a nice day! :)
-Charlie