Question 508545
ax + b = cx - d

Get common terms together.

ax - cx = -b - d

Factor out an x.

x(a-c) = -(b+d)

x = -(b+d) / (a-c) <---- answer

By our first answer, 2x + 9 = 7x -1 where a=2, b = 9 , c =7 and d = 1 then


-(9+1)/(2-7) =  -10/-5 =  2

x = 2. <----- answer