Respuesta :

Answer:

17 = k

Step-by-step explanation:

d(x) = 7x – k

Let  d(3) = 4

4 = 7*3 -k

4 = 21 -k

Subtract 21 from each side

4 -21 = 21-k-21

-17 = -k

Multiply each side by -1

17 = k

Answer:

k=17

4= 7*3 -k

k=21-4

k= 17