If a + b - c = 2d, and if a - b + c =-2e, then a = Choose the correct choice from the following choices.
A) 2(d + e)  B) d – e  C) (d + e)/2  D) d-2e  E) e-d
Add both equations:   a + b - c = 2d   a - b + c =-2e   a+b-c+a-b+c=2d-2e   2a=2d-2e   a=(d-e)   Ans:d – e
<result>B</result>
If a + b - c = 2d, and if a - b + c =-2e, then a =