Answer:
The answer is: small+large.
Step-by-step explanation:
If the variable of the smaller sheetrock is stored in small:
var small.
And the variable of the larger sheetrock is stored in large:
var large.
The length of the wall will be the sum of the two pieces of sheetrock:
For example:
var small = 5;
var large = 10;
small+large = 5 + 10 = 15 is the length of the wall.