If `k (x) =5x +2,` what is the vlaue of ` k (4) - k(1)` ?

Options

A. 15
B. 17
C. 19
D. 21

Explanation

To solve the question, we need to find the value of \( k(4) - k(1) \) given that \( k(x) = 5x + 2 \).

### Step-by-step solution:

1. **Calculate \( k(4) \)**:
\[ k(4) = 5 \cdot 4 + 2 \]
\[ = 20 + 2 \]
\[ = 22 \]

2. **Calculate \( k(1) \)**:
\[ k(1) = 5 \cdot 1 + 2 \]
\[ = 5 + 2 \]
\[ = 7 \]

3. **Subtract \( k(1) \) from \( k(4) \)**:
\[ k(4) - k(1) = 22 - 7 \]
\[ = 15 \]

### Final Answer:
The value of \( k(4) - k(1) \) is \( 15 \).

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