As a property of equations, you can add or subtract the same quantity to/from both sides, and the truth value of the equality will remain the same: if you start with something true, e.g. 7=7 and add the same quantity to both sides, e.g. 7+4=7+4, you will still have something true, i.e. 11=11.
On the other hand, if you start with something false, e.g. 3=7 and add the same quantity to both sides, e.g. 3+6=7+6, you will still have something false, i.e. 9=13.
So, you can subtract
from both sides to transform the equality into

as required.
Answer:
5/9
Step-by-step explanation:
1/3=3/9
3/9+2/9=5/9
Does it have multiple choice?
If it does not i can give you my answer but idk how they want it to be written or to be simplified.
Answer:
Option D : $780 is the correct answer.
Step-by-step explanation:
Given expression is:
E = $500 + $7x
We will put all the values of given options to check.
A. Putting 430 in given expression
430 = 500 + 7x
430 - 500 = 7x
-70 = 7x
As the number of items sold cannot be negative, therefore, this option is not correct.
B. 530 = 500 + 7x
530 - 500 = 7x
30 = 7x
x = 4.3 (By dividing both sides by 7)
Which is not a whole number.
C. 680 = 500 + 7x
680 - 500 = 7x
7x = 180
x = 25.71
Which is also not a whole number.
D. 780 = 500 + 7x
780 - 500 = 7x
280 = 7x
7x = 280
x = 40
Which is a whole number.
Hence,
Option D : $780 is the correct answer.
5.55 = 5 55/100 = 555/100 = 111/20