Question

15c + 45 - 12 = 78пОМОГИТЕ РЕШИТЬ

Answer 1

15с+45-12=78
15с=78-45+12
15с=45
с=45:15
с=3

Answer 2

15с+45-12=78; 15с+33=78; 15с= 78-33; 15с=45; с= 45:15; с= 3.