Answer:
Because z is the unknown that we need to find, we treat t and a as constants (or numbers).
a(t+z)= 45z+67
⇒ at+ az= 45z+ 67 (distributive property)
⇒ at- 67= 45z- az
⇒ at- 67= z(45- a) (distributive property)
⇒ (at -67)/ (45- a)= z
Final answer: z= (at- 67)/ (45- a)
