Which of the following expressions has 3 terms?

8x + y - z

xyz

y^3 + 1

the first

first

To determine which of the given expressions has 3 terms, we need to count the number of distinct terms within each expression.

1. 8x + y - z:
To count the terms in this expression, we identify the distinct variables or variable combinations separated by the plus (+) or minus (-) signs. In this case, we have three distinct terms: 8x, y, and -z.

2. xyz:
In this expression, xyz is a single term since there are no mathematical operations or symbols separating the variables x, y, and z.

3. y^3 + 1:
Similar to the first expression, we identify the distinct terms separated by the plus sign. In this case, we have two distinct terms: y^3 and 1.

Therefore, the expression "8x + y - z" has 3 terms, as it contains three distinct variable combinations separated by plus and minus signs.