How would you work out the linear equation (7x-5) - (x-4) + (3x-8) = 3x-5?

First take the brackets away so:

7x-5 - x+4+3x-8 = 3x-5

do the additions and subtractions:

9x-9 = 3x-5

isolate x to one side (remember they switch signs when they switch sides):

9x-3x = - 5+9

add and subtract

6x = 4

solve for x:

x = 4/6