Solve for y: -

78 + y = 523

y = ?

you so much! : )

To solve for y we need to use d INVERSE OPERATION of addition which is subtraction. Then we will check our work:-
 
Lets do it:-
 
78 + y = 523
523 - 78 = 445
y = 445
 
CHECK OUR WORK:-
 
78 + y = 523
y = 445
78 + 445 = 523
We were RIGHT!!
 
So, y = 445
 
Hope I helped ya!! xD

78 + y = 523

Now, first lets start out by applying the inverse operation to isolate the variable.

78 + y = 523
-78         -78           ⇒  Inverse operation

523 - 78 = 445      

y = 445                   ⇒ We have our value for y

CHECK OUR WORK:-

78 + 445 = 523
523 = 523

Our answer is correct. 

The answer is a. yes, it asks a question that can be answered correctly (by measuring hands).