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2 years ago

Find the sum of the first 6 terms of geometric series 2-10+50+.....

Mathematics

1 answer:

barxatty [35]2 years ago

8 0

<h3>Answer: -5208</h3>

============================================

Work Shown:

term1 = 2

term2 = -10

term3 = 50

term4 = -250

term5 = 1250

term6 = -6250

Each new term is found by multiplying the previous term by -5

Add up the terms

2 + (-10) + 50 + (-250) + 1250 + (-6250) = -5208

-------------

A shortcut is to use a = 2, r = -5 and n = 6 in the formula below

Sn = a*(1-r^n)/(1-r)

S6 = 2*(1-(-5)^6)/(1-(-5))

S6 = 2*(1-15625)/(1+5)

S6 = 2*(-15624)/6

S6 = -31248/6

S6 = -5208

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Is 16x^2-56x+49 a perfect square trinomial? How do you know ? If it is, factor the expression. Please show your work

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Answer:

yes
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Step-by-step explanation:

If it is, the first and last terms are perfect squares, and the middle term is twice the product of the roots of those squares.

16x^ = (4x)^2 . . . . a perfect square

49 = 7^2 . . . . . . . a perfect square

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2 years ago

What is 57.2 times 56.4

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Step-by-step explanation:

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2 years ago

Read 2 more answers

Circle A has a diameter of 9 inches, a circumference of 28.26 inches, and an area of 63.585 square inches. The diameter of circl

torisob [31]

Please note that pi has just one value. The only difference stems from round-off error when you don't use all of the digits following "3.14159 ... " to represent the value of pi. The formula for circumference is C = 2 pi r, or C = pi d,
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2 years ago

The table below shows the relationship between the number of calories burned and the minutes of exercise.

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Answer:

Option B

Step-by-step explanation:

Since, number of calories 'C' burned is proportional to the number of minutes (m) given to the exercise,

C ∝ m

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Where k is the proportionality constant.

From the table attached,

For C = 250 calories and m = 30 minutes,

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2 years ago

The minute hand of a clock is exactly 6in in length, and the tip of the minute hand has traveled ten inches since noon. What tim

frutty [35]

$\bf \textit{arc's length}\\\\
s=\cfrac{\theta \pi r}{180}\qquad 
\begin{cases}
r=radius\\
\theta =angle\ in\\
\qquad degrees\\
------\\
r=6\\
s=10
\end{cases}\implies 10=\cfrac{\theta \pi 6}{180}\implies \cfrac{180\cdot 10}{6\pi }=\theta 
\\\\\\
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now, the circle of the clock has 360°, if we divide it by 60(minutes), we get 360/60, just 6° for each minute.

now, if there are 6° in 1 minute, how many minutes in 95.49°?

well, just 95.49/6 or about 15.92 minutes, I take it you can round it up to 16 minutes.

so 16 minutes since noon, so is about 12:16, about time get the silverware for lunch.

3 0

3 years ago