Hello!
The answer would be d = 10. Solve it like this. (v v v)
10 * 0 + 4 * d = 40 ---> 0 + 4 * 10 = 40
0 + 40 = 40
40 = 40
Hope this helps! ☺♥
subtract 14 from 22 to isolate the variable
Answer:

Step-by-step explanation:
Considering the expression

Lets determine the expansion of the expression




Expanding summation








as





so equation becomes


Therefore,
Answer:
the answer would be d
Step-by-step explanation: