a) x + 5 = 15
Subtracting 5 from both sides, we get:
x + 5 - 5 = 15 - 5
x = 10
Therefore, the solution is x = 10.
b) 12 – y = 12
Subtracting 12 from both sides, we get:
12 - 12 - y = 12 - 12
-y = 0
Multiplying both sides by -1, we get:
y = 0
Therefore, the solution is y = 0.
c) 3a = 27
Dividing both sides by 3, we get:
a = 9
Therefore, the solution is a = 9.
d) y/4 = 20
Multiplying both sides by 4, we get:
y = 80
Therefore, the solution is y = 80.
e) 2 + y = 0
Subtracting 2 from both sides, we get:
y = -2
Therefore, the solution is y = -2.