Answer:
n = 9
Step-by-step explanation:
20 + 18 + ... + 6 + 4
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a = 20 ; d = -2 ; n = ?
--------
4 = 20 + (n-1)(-2)
-16 = (n-1)(-2)
---------
n-1 = 8
n = 9
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S(9) = (9/2)(20+4)
S(9) = 4.5*24
S(9) = 108
Answer:
n=-4
Step-by-step explanation:
n=56/-14
n=-4
Answer:
x = 12
Step-by-step explanation:
Quadrilaterals ABCD and FECG are similar, so their corresponding sides would be in the proportion.

No because a pentagon has more sides than a square does.
to find perimeter you have to add up all the sides.
for the square it would be 9+9+9+9 which is 36
for the pentagon it would be 9+9+9+9+9 which is 42.