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3 years ago

Write an explicit formula fo the sequence 7,2,-3,-8,-13.... Then find the 14th term

Mathematics

1 answer:

MrRa [10]3 years ago

6 0

Answer:

The 14th term is -58

Step-by-step explanation:

The formula for an arithmetic sequence is

an = a1+d(n-1)

where a1 is the first term

d is the common difference and

n is the term number

a1 = 7

d = 2-7 = -5

Check -3-2 = -5 so d = -5

an = 7 -5(n-1)

We want the 14th term

a14 = 7 -5(14-1)

a14 = 7 -5(13)

a14 = 7 -65

a14 = -58

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Evaluate the determinant for the following matrix: [- 5 1 1 4] A. –21 B. 19 C. –17 D. –24

mariarad [96]

Answer:

-21

Step-by-step explanation:

I assume this is a 2 by 2 matrix.

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determinant = -5 * 4 - 1 * 1 = -20 - 1 = -21

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3 years ago

Read 2 more answers

A retailer sold an electric item to a customer at a loss of 10 percent the customer purchase it for rs 25425 including 13, perce

Mashutka [201]

Answer: Rs 25,000

Step-by-step explanation:

Given

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2 years ago

The question says “The image shows the front of Bob’s barn.Bob plans on painting the front of his barn,not including the doors o

AleksandrR [38]

Bob need to paint 205 square feet.

Solution:

Length of the door = 7 ft

Breadth of the door = 5 ft

Area of the door = length × breadth

= 7 × 5

= 35

Area of the door = 35 ft²

The given image is a trapezoid.

Top base = 12 ft

Bottom base = 20 ft

Area of the trapezoid = $\frac{1}{2} \times\text{sum of the parallel sides}\times\text{height}$

$$=\frac{1}{2}\times(12+20)}\times15$

$$=\frac{1}{2}\times 32\times15$

= 240

Area of the trapezoid = 240 ft²

Surface area to paint = Area of the trapezoid – Area of the door

= 240 ft² – 35 ft²

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Hence Bob need to paint 205 square feet.

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3 years ago

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Elanso [62]

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3 years ago

What is the solution set of the quadratic equation 8x2 +2x +1 =0?

Sidana [21]

$\displaystyle\\
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4 0

3 years ago