Question

–x – 7 = 16 please help me

Answer 1

-x-7=16 |+7 , add to both sides
-x=23 |*(-1)
x = -23

Answer:
-23
,,,,,,,,,,,,,,,,,,,,
-x-7=-(-23)-7=23-7=16

Answer 2

Move the -7 to the right, its sign will flip (do you know why?)
Negate both sides to change -x to x

-x = 16+7
-x = 23
x = -23