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2 years ago

What is the sum of the first seven terms of the geometric series where a1 = 10 and r = −2?

Mathematics

1 answer:

matrenka [14]2 years ago

4 0

$Sum_{7} = 10 * \frac{1- (-2^{7}) }{1 - (-2)} = 10* \frac{1+128}{1+2} = 10* \frac{129}{3} = 10 * 43 = 430$

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kykrilka [37]

$\vec F$ has divergence

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3 years ago

You and your best friend go out to dinner. The server was so good that you want to leave a 20% tip. Your food bill was $25.50. W

lys-0071 [83]

Answer:

$5.10

Step-by-step explanation:

We need to find 20% of 25.50

Multiply 20% * 25.50

Change to a decimal

.20 *25.50

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6 0

3 years ago

A walking path across a park is represented by the equation y= -3x - 6 . A new path will be built perpendicular to this path. Th

Romashka [77]

Answer:

The equation that represents the new path is y=(1/3)x+4

Step-by-step explanation:

step 1

Find the slope of the give line

we have

y=-3x-6

the slope m is equal to

m=-3

step 2

Find the slope of the perpendicular line to the given line

Remember that

If two lines are perpendicular, then their slopes are opposite reciprocal of each other

we have

m=-3 -----> slope of the given line

therefore

The slope of the perpendicular line is equal to

m=1/3

step 3

With m=1/3 and the point (-3,3) find the equation of the line

y-y1=m(x-x1)

substitute

y-3=(1/3)(x+3)

y=(1/3)x+1+3

y=(1/3)x+4 -----> equation that represent the new path

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3 years ago

A square has a perimeter of 12 cm. What is its area?

Zigmanuir [339]

a. 9 cm 2 because each side would be 3 and length x width would be 3 x 3 = 9

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3 years ago

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A frame is marked down by 22 percent from an original price of $14.50. What is the new price?

nydimaria [60]

Answer:

$11.31

Step-by-step explanation:

$14.50x .22= 3.19

$14.50- 3.19= 11.31

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2 years ago

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