Show the tens fact you used. show the difference. 14-6= 10-? =?

(a) The first one in these items, we are to directly determine the difference between 14 and 6. The answer to this is 8. 

(b) In this item, we are to find out or determine the number that when subtracted from 10, will yield the same number. If we let x be this number then,
   10 - x = x

Simplifying the equation,
  10 = 2x
Dividing both sides by 2 will give us an answer of 5. 

ANSWERS: (a) 8
                     (b) 5

Divide 40%5 and your answer is 8

Iwould say d but i am not 100% positive