Don't know how to do this

simplify each expression by combining terms

Combining like terms is actually pretty straightforward, you just have to combine like terms. In the problem 5c+2c, it would equal 7c since c is a common variable in this equation.

In the next question 16p+5+p-3x+6-x, it would equal 17p-4x+11 because 16p+p is 17p, -3x-x is -4x, and 5+6 equals to 11.

In the third question 18p+3-8p-5 would equal to 10p-2 since 18p-8p equals to 10p, and 3-5 equals to -2.

In the last question 9u+11v-22u+12v, it would equal to -13u+23v because 9u-22u equals to -13, and 11v+12v is 23v.

I hope this helped you!

it would open into a square depending on the type of envelope i’m not sure about the second part