Answer:
32
Step-by-step explanation:
Let Peter's number = p
(Peter's number - 17) * - 3 = - 45
(p - 17) * - 3 = - 45
Open the bracket
-3p + 51 = - 45
-3p = - 45 - 51
-3p = - 96
Divide both sides by -3
-3p/ -3 = - 96/ - 3
p = 32
Hence, Peter's number is 32
