jawab dong plisss yg bener ya

1) a) x + 12 = 15
b) ¼ c = 5

2) 2x - 1 = 5
2x = 5 + 1
2x = 6
x = 3

3) a) x + 5 = 7
x = 7 - 5
x = 2
b) 9 = x - 3
x = 9 + 3
x = 12