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3 years ago

1/2,-4,32,-256 find an explicit formula for the sequence

Mathematics

2 answers:

Anna11 [10]3 years ago

4 0

Answer:

.5(−8)^n−1

Step-by-step explanation:

Veseljchak [2.6K]3 years ago

3 0

This is a geometric sequence where each term after the first is found by multiplying the previous one by a fixed, non-zero number called the common ratio.

an = a1 * r^n-1
where
an = nth term
a1 = 1st term
r = common ratio

In this problem, a1 = 1/2.

Find the common ratio by dividing -4 by 1/2 to get r = -8.

The explicit formula is an = (1/2)*(-4)^n-1

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A jogger begins her workout by jogging to the park, a distance of 21 miles. She then jogs home at the same speed, but along a

Luba_88 [7]

Answer:

She jogs at a speed of 7mph

Step-by-step explanation:

Distance to the Park=21 miles

Let her Speed be r( miles/hour)

Time taken= t hour

Therefore her Speed, r= 21/t .....(I)

Distance on her Return Trip= 28 miles

On her return trip, the time is 1 hour longer, therefore time taken=(t+1) hour

Speed , r =28/(t+1) ........(ii)

Since her speed is the same

21/t=28/(t+1)

Cross Multiplying

21(t+1)=28t

21+21t=28t

21=28t-21t

21=7t

Therefore her time, t=3

From (I),

Speed r= 21/t= 21/3 =7 miles per hour

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3 years ago

What is the perimeter of (-6, 2), (3,2), (-6,-7) (3,-7)

blagie [28]

Hello! So just by looking at the points, I already know that it’s gonna be a square. This is because when we look at the coordinates, The difference if -6 And 3 is 9 And the difference between 2 and -7 is 9. With that being said, each side is 9 inches apart. There are 4 sides. Multiply the length of the sides by 4. 9 * 4 = 36. The perimeter of the square is 36 units.

7 0

4 years ago

Select the correct answer.

Nookie1986 [14]

Answer:

Correct option: C.

Step-by-step explanation:

(Assuming the correct function is R(x) = 2x^2 + 3x + 5)

To find the input value that gives the value of R(x) = 19, we just need to use this output value (R(x) = 19) in the equation and then find the value of x:

$R(x) = 2x^2 + 3x + 5$

$19 = 2x^2 + 3x + 5$

$2x^2 + 3x -14 = 0$

Solving this quadratic function using the Bhaskara's formula (a = 2, b = 3 and c = -14), we have:

$\Delta = b^2 - 4ac = 9 + 112 = 121$

$x_1 = (-b + \sqrt{\Delta})/2a = (-3 + 11)/4 = 2$

$x_2 = (-b - \sqrt{\Delta})/2a = (-3 - 11)/4 = -3.5$

So looking at the options, the input to the function is x = 2

Correct option: C.

3 0

3 years ago

Write and solve an equation to find the value of x. PLSS HELP

natima [27]

Answer & Step-by-step explanation:

Vertical angles are congruent meaning that these two angles are going to have the same measurement. Since we know this, then we can set up an equation where one angle is equal to the other.

x + 10 = 55

Subtract 10 on both sides of the equation.

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8 0

3 years ago

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podryga [215]

Answer:

-3 $\leq$ x matches with 6,

3 < x matches with 5,

x $\geq$ 3 could not simplify any further

x < 3 could not simplify any further

x $\leq$ -3 could not simplify any further

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Step-by-step explanation:

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5 0

3 years ago