Answer:
Step-by-step explanation:
We have a geometric sequence with:
,
, and
Where
Sn is the sum of the sequence
r is the common ratio
is the first term in the sequence
n is the number of terms in the sequence
The formula to calculate the sum of a finite geometric sequence is:
Then:
Now we solve for
Answer:
4 ft.
Step-by-step explanation:
We can consider the orignial square's sides to be x, so area of the original figure:
The new rectangle's sides will be x and x+8, so the area of the new figure will be x^2+8x.
We know that the new area is 3 times the old one. So our equation will be:
x^2+8x=3x^2
our answer will be x=4.
Therfore, the length of the side of the old flower bed is 4 ft.