If you add 9+4 you get 13 so Melissa has 13 stamps now :)
Step-by-step explanation:
Let the total amount of salary be X, then
3/10X + 2/3X + amount left= his salary(X)
(9X + 20X)/ 30 + 2100 = X
29X/30 - X = -2100
(29X - 30X)/30 = -2100
by cross multiplying
-X = -2100×39
-X = -81900
divide both side by -1
X = 81900.
therefore his salary = 81900
The answer would be 3
(Let me know if you want me to explain)
Hope this helps
Have a great day/night
-2x+5x = 3x
so answer would be C 4x^2+3x-7