The given equation is

And we have to solve for y.
Solving for y, means isolating y . And to isolate y, we need to get rid of 4 that is with y .
It means we have to separate 4 from y, and for separation , we have to perform division. That is, we have to divide both sides by 4, and that will be the next step .
So out of the four options, correct option is the last option .
Answer:
7
Step-by-step explanation:
Given that there are 5 number cards.
They are 2,5,7,8,9
Total of all numbers in the cards = 2+5+7+8+9= 31
One card is removed say with number x.
Now sum new would be =31-x .. i
Average of remaining 4 cards = 6
So sum of remaining 4 cards = 6(4) = 24 ... ii
i and ii represent the sum of remaining 4 cards. Hence they should be equal
31-x =24
Subtract 31 from both sides to get
-x=-7
Or x =7
<u>Define x:</u>
Let the first number be x.
1st number = x
2nd number = x + 1
3rd number = x + 2
<u>Construct equation:</u>
x + x + 1 + x + 2 = 4(x + 1)
3x + 3 = 4(x + 1)
Answer: 3x + 3 = 4(x + 1)