(-7+p)(8+p)

I don't understand this at all.

To simplify the expression (-7+p)(8+p), you can use the distributive property.

First, distribute the -7 to both terms inside the parentheses:

(-7)(8) + (-7)(p)

This gives you -56 - 7p.

Next, distribute the p to both terms inside the parentheses:

(8)(p) + (p)(p)

This gives you 8p + p^2.

Now, you can combine the like terms:

-56 - 7p + 8p + p^2

Simplifying further, you get p^2 + p - 56.

So, the simplified expression is p^2 + p - 56.