Simplify -3p 3 + 5p + (-2p 2) + (-4) - 12p + 5 - (-8p 3). Select the answer in descending powers of p.?

-3p³ + 5p + (-2p²) + (-4) - 12p + 5 - (-8p³)
= -3p³ + 5p - 2p² - 4 - 12p + 5 + 8p³
= (-3p³ + 8p³) - 2p² + (5p - 12p) + (-4 + 5)
= 5p³ - 2p² - 7p + 1

For p cubed use:
p^3
or
p³

For p squared use:
p^2
or
p²

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Why?
A lot of time we use 'x' as a variable.
What is 3x3? 9 or 3x³ ?? You see the problem.

You can copy and paste the ² and ³ symbols, or simply use ^

I'm going to guess what your original expression was. It's normal to use ^ in front of a superscript, like an exponent, in typewritten expressions. So "p raised to the third power" is typed as p^3. With that understanding, your expression looks like:

-3p^3 + 5p + (-2p^2) + (-4) - 12p + 5 - (-8p^3)

First simplify the terms:

= -3p^3 + 5p - 2p^2 - 4 - 12p + 5 + 8p^3

Combine like terms (I'm doing this in order of appearance):

= (-3 + 8)p^3 + (5 - 12)p - 2p^2 + (-4 + 5)
= 5p^3 - 7p - 2p^2 + 1

Finally, put in standard form (exponents in descending order)

= 5p^3 - 2p^2 - 7p + 1