Answer:
I think it's 70
Step-by-step explanation:
i did 560/2 and got 280 and then divided 280 by 4 and got 70
For both problems, we can use the section formula.
1) 
2) 
C cause 9 and 243 are the suplies and 4 and x are the number of houses that can be made
Use Pythagoras's theorem.

Now, minus 12 from 15:
15 - 12 = 3,
which you need to square.
So the length of a = 9cm.
You can also do:

Which gets 9.
Hope this helps.