Answer:
1. x = 18.4
2. x = -1.25
3. x = 
4. x = 12.3
5. x = 6.4
6. z = 5.8
7. x = 
8. x = -
9. x = 
10. x = -9
11. z = 18
12. x = 7
13. x = -9
14. x = -36
15. x = -7
16. x = 8
17. z = -1.5
18. x = -
19. x = 16
20. x = -12
21. x = 
22. x = -1.6
23. x = 1.8
24. x = -8.2
Step-by-step explanation:
1. x - 3.5 = 14.9 (add 3.5 to each side)
x = 18.4
2. x + 2.25 = 1 (subtract 2.25 from each side)
x = -1.25
3. - = x -
 = x -  (add
 (add  to each side)
 to each side)
 -
 -  = x (multiply
  = x (multiply  by
 by  and
 and  by
 by  to get a common denominator)
 to get a common denominator)
 -
 -  = x
 = x
 = x
 = x
4. x - 2.8 = 9.5 (add 2.8 to each side)
x = 12.3
5. x - 8.5 = -2.1 (add 8.5 to each side)
x = 6.4
6. z - 9.4 = -3.6 (add 9.4 to each side)
z = 5.8
7. x +  =
 =  (subtract
 (subtract  from each side)
 from each side)
x =  -
 -  (multiply
 (multiply  by
 by  to get a common denominator)
 to get a common denominator)
x =  -
 - 
x = 
8. - + x = -
 + x = - (add
 (add  to each side)
 to each side)
x =  -
 -  (multiply
 (multiply  by
 by  to get a common denominator)
 to get a common denominator)
x =  -
 - 
x = - = -
 = -
9. x -  =
 =  (add
 (add  to each side)
 to each side)
x =  +
 +  (multiply
 (multiply  by
 by  to get a common denominator)
 to get a common denominator)
x =  +
 + 
x =  =
 =  =
 = 
10. x + 6 = -3 (subtract 6 from each side)
x = -9
11. z - 7 = 11 (add 7 to each side)
z = 18
12. -1 = x - 8 (add 8 to each side)
7 = x
13. -4x = 36 (divide each side by -4)
x = -9
14. - = 12 (multiply each side by -3)
 = 12 (multiply each side by -3)
x = -36
15. 63 = -9x (divide each side by -9)
-7 = x
16. 6.4 = 0.8x (divide each side by 0.8)
8 = x
17. -2.8z = 4.2 (divide each side by -2.8)
z = -1.5
18. - x = 5 (divide each side by -
x = 5 (divide each side by - )
)
x =  ÷ -
 ÷ -
x =  (times) -
 (times) -
x = -
19.  x = 8 (divide each side by
x = 8 (divide each side by  )
)
x = 16
20. - x = 9 (divide each side by -
x = 9 (divide each side by - )
)
x = -12
21. - x = -
x = - (divide each side by -
 (divide each side by - )
)
x = - ÷ -
 ÷ -
x = - (times) -
 (times) -
x =  =
 =  =
 = 
22. 1.6x = -3.2 (divide each side by 1.6)
x = -1.6
23. - = -
 = - x (divide each side by -
x (divide each side by - )
)
1.8 = x
24. -2.5x = 20.5 (divide each side by -2.5)
x = -8.2