8z − 4 = 7z
move 8z to the other side
sign changes from +8z to -8z
8z-8z-4=7z-8z
-4= 7z-8z
-4= -z
mutiply both sides by -1 to get +z
(-4)(-1)= (-z)(-1)
Answer:
z= 4
you collect the like terms
8z -4=7z
-4=7z -8z
-4=-z
menus cancel menus
Z=4//
