#7
2,4,8,16
15,30,60,120
#9
1,2,3,
4,8,12
The perimeter of R is the same as the perimeter of L
This is an arithmetic series, so we know, that:
Sum = (First term + Last term) * Number of terms /2
Here we have:
First term = 33
Last term = 104
Number of terms = 104 - 33 + 1 = 72
and
Check the attachment for the answers. Click on it again to make it bigger.
Anything in the negatives like -2*2=-4-1 = -5
Or positive values up to 5
2*5=10-1=9