If the formula is a+b-c then you need to substitute the letters with the numbers. For this equation the formula would be:
(1+3-4) + (2+5-6)
(4-4) + (7-6)
0 + 1
=1
The answer would be 1
<span>If line m is parallel to line k, then it has a slope of C)2/3</span>
With g=3
Just replace every g with a 3.
So the equations becomes:
12g·(9÷g)=12(3)·(9÷(3))
This can also be written in the form:

Cancelling out the 3's:
12·9=108