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3 years ago

what is the sum of an 8th term geometric series if the first term is -11, the last term is 180,224, and the common ratio is -4

Mathematics

1 answer:

Mumz [18]3 years ago

4 0

The sum of n terms is given from the first term and the common ratio by

$S_{n}=a_{1}\dfrac{r^{n}-1}{r-1}$

For your given values of a1=-11, r=-4, n=8, the sum of 8 terms is

$S_{8}=(-11)\dfrac{(-4)^{8}-1}{-4-1}=(-11)\dfrac{65535}{-5}\\\\=144177$

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Answer:

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now, the easiest one will be when the vertices are on the coordinate axes.

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3 years ago

The bases of a trapezoid are 16.8 yards and 6.9 yards. If the height is 2 yards, what is the area of the trapezoid?

Svet_ta [14]

Hello,
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A=1/2(b1+b2)×h
Where b1 represent big base
b2 represent small base
and h represent height
Now, we just need to replace the number to get the final answer:
A=1/2(16.8+6.9)×2
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OverLord2011 [107]

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