Answer:
A
Explanation:
Isolate the variable y in each equation
A.
y + 2.9 = 8
To isolate y, subtract both sides by 2.9
y = 5.1
This equation has y = 5.1
Let's check the other equations just to get a better understanding of how to do it
B.
y - 11 = 5.1
To isolate y, add both sides by 11
y = 16.1
This equation does not have y = 5.1
C.
y + 4.2 = 5.2
To isolate y, subtract both sides by 4.2
y = 1
This equation does not have y = 5.1
D.
24 - y = 19.2
To isolate y, subtract both sides by 24
-y = -4.8
To isolate y, divide both sides by -1
y = 4.8
This equation does not have y = 5.1