This is a lot of questions-
I did them all on a calculator.
1.)
3x - 4 + 6x = -31
3x + 6x - 4 = -31
9x - 4 = -31
9x = -27
Answer: x= -3
2.)
17 = 3x - 10
3x -10 = 17
-10 = -10
3x = 27
divide both sides by 3
Answer: x= 9
3.)
2x + 6 = 4x - 8
-6 = -6
2x = 4x -14
-4x (both sides)
-2x = -14
divide both sides by -2
Answer: x = 7
4.)
17x - 5(3x - 11) = 41
2x +55 = 41
-55 (both sides)
2x = -14
divide 2 both sides
Answer: x = -7
5.)
5x - (3x - 6) = 18
2x + 6 = 18
-6 both sides
2x = 12
divide both sides by 2
Answer: x = 6
6.)
6x - 3(4 - 5x) = 30
21 - 12 = 30
+12 boh sides
21x = 42
divide both sides by 21
Answer: x = 2
7.)
x - (-5) = 7
x + 5 = 7
-5 both sides
Answer: x = 2