Question

For the equation x + y = 3. How many possible values for x are there if x and y are both whole numbers?

Answer 1

Answer:

A

Step-by-step explanation:

Because it is 2+1 and 3+0, those are the only solution, therefore A is correct

Answer 2

Answer: C) 4

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Explanation:

The set of whole numbers is {0, 1, 2, 3, ...}

So we include 0 and any positive number that doesn't have decimal or fractional components to it. Negative values are not included.

• If we plug in x = 0, then x+y = 3 solves to y = 3
• If we plug in x = 1, then x+y = 3 solves to y = 2
• If we try x = 2, then x+y = 3 solves to y = 1
• Lastly, x = 3 leads to y = 0

Whatever you pick for x, the y value must add to it to get 3. Both x and y must be numbers from the set of whole numbers.

There are four cases shown in the bullet points above, so we have four different solutions. We can't move onto x = 4 because the y solution would be y = -1, but -1 is not in the set of whole numbers.