III. Translate each sentence into algebraic expression
16. A number increased by four is twelve.
17. a number decreased by nine is equal to eleven.
18. Five times a number is fifty.
19. Three times a number increased by six is fifteen.
20. thirty is equal to twice a number decreased by four.​


Sagot :

Answer:

x+4=12

x-9=11

5x=50

3x+6=15

30=2x-4