Final answer:
For x=5, the expressions 4x and 15+x both equal 20, so they have the same value. However, they are not equivalent expressions because their values will not match for all values of x, as the expressions are structurally different.
Step-by-step explanation:
The question asks whether the expressions 4x and 15+x are equivalent or have the same value when x is 5.
To determine if they have the same value when x is 5, we substitute 5 into both expressions:
- 4x = 4(5) = 20
- 15+x = 15+5 = 20
When x is 5, both expressions equal 20, so they have the same value.
However, to determine whether the expressions are equivalent in general, we need to consider any value of x. Equivalence means the two expressions will have the same value for all values of x, not just when x is 5. By looking at the forms of the expressions, 4x varies directly with x, while 15+x is a linear expression with a constant term and a variable term. As x changes, the values of these expressions will not always match; therefore, they are not equivalent expressions.