Step-by-step explanation:
1) -5n+10n
= 5n
2) -x-9+2x-10
= 2x-x-9-10
= x-19
3) -5(x-10)-x
= -5x+50-x
= -6x+50
4) 9-5(1-7x)
= 9-5+35x
= 35x+4
5) y^2-x
= 3^2-2
= 9-2
= 7
Do the remain questions by yourself, you can do it!
