Originally Posted by dianna
CaptainBlack and topsquark have already explained how to solve those equations. Look here: http://www.mathhelpforum.com/math-he...-equation.html
If you are not certain what to do use the following method:
Use this method to solve the next 2 equations.
d - 4 = 7
+ 4 | +4 add 4 on both sides
-------------- to get rid of the -4
d = 11
(For confirmation only: c = 54; a = -14)
PS.: You have published 10 more or less identical problems without a hint how we can help you. So I'm not quite certain that I could help you with this post.