Answer:
17c + 9 = 10c + 9 - 7c
COMBINE LIKE TERMS
10c + 7c = 17c
9 IS NOT A LIKE TERM, SO WE LEAVE IT ALONE
D+Q=61 => D=61-Q
3+D=Q
10D+25Q=1090
10(61-Q) + 25Q=1090
610-10Q+25Q=1090
610+15Q=1090
-610 -610
15Q=480
480/15=32
32 quarters
Answer:
The element you add is 
Step-by-step explanation:
The element you add is 
Remember that

So, in order to complete the square you add 
But when you multiply times
you get

We start as 4 8 12 16 20 24that are all divided into the fourth