Respuesta :

First of all, move the known term (-9) at the left of the equal with changed sign.

5z = 36+9

5z = 45

Divide both terms by 5

5z/5 = 45/5

z = 9
5z - 9 = 36

add 9 to both sides

5z - 9 + 9 = 36 + 9

5z = 45

divide both sides by 5

5z / 5 = 45 / 5

z = 9