Multiply everything in the parenthesis by a.
ac + ab = d
Subtract ab from both sides.
ac = d - ab
Divide a on both sides.
c = d - ab / a
Hope this helps!
The number of rows in the arena is 26
<h3>How to determine the number of rows?</h3>
The hockey arena illustrates an arithmetic sequence, and it has the following parameters:
- First term, a = 220
- Sum of terms, Sn = 10920
- Common difference, d = 16
The number of rows (i.e. the number of terms) is calculated using:

So,we have:

Evaluate the terms and factors

Evaluate the like terms
21840 = n(424+ 16n)
Expand
21840 = 424n + 16n^2
Rewrite as:
16n^2 + 424n - 21840 = 0
Using a graphical tool, we have:
n = 26
Hence, the number of rows in the arena is 26
Read more about arithmetic sequence at:
brainly.com/question/6561461
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Answer:
Depends on the type of rope but I would say feet
Step-by-step explanation:
Surface area of cone is a sum of surface of its base and surface of its mantle.
Surface of its base is a circle which surface we will calculate like this:
Sb = pi*r^2 where r is d/2
Sb = 201m^2
Surface of mantle we calculate by:
Sm = pi*l*r where l is length of side of cone.
l =

= 25.3
Sm = 635.8m^2
Total suface is:
Sb + Sm = 836.8m^2
Answer:
x=8
Step-by-step explanation: