What is the standard deviation of the data set 2,4,7,8,9

2. The path of a high diver is given by y = + (2x2 – 9x – 56), where y is the height of the diver

timofeeve [1]

Answer:

The diver will be 8 feet from the end of the board when he hits the water.

Step-by-step explanation:

The diver hits the water when y = 0.

To find the distance, we have to find the values of x when y = 0.

Solving a quadratic equation:

Given a second order polynomial expressed by the following equation:

$ax^{2} + bx + c, a\neq0$ .

This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = (x - x_{1})*(x - x_{2})$ , given by the following formulas:

$x_{1} = \frac{-b + \sqrt{\bigtriangleup}}{2*a}$

$x_{2} = \frac{-b - \sqrt{\bigtriangleup}}{2*a}$

$\bigtriangleup = b^{2} - 4ac$

In this problem, we have that:

$y = 2x^{2} - 9x - 56$

$2x^{2} - 9x - 56 = 0$

So

$a = 2, b = -9, c = -56$

Then

$\bigtriangleup = b^{2} - 4ac = (-9)^{2} - 4*2(-56) = 529$

$x_{1} = \frac{-(-9) + \sqrt{529}}{2*2} = 8$

$x_{2} = \frac{-(-9) - \sqrt{529}}{2*2} = -3.5$

It is a horizontal distance, so the answer is a positive value.

The diver will be 8 feet from the end of the board when he hits the water.

7 0

3 years ago

............°_°.............

Rasek [7]

Answer:

3/4 and 0.95 would both result in a reduction.

Step-by-step explanation:

multiplying by anything less than 1 will make it smaller which both 3/4 and 0.95 are smaller than 1.

8 0

3 years ago

Read 2 more answers

Write a linear equation in the form y=mx+b given the following two points.

IRINA_888 [86]

Answer:

D. y=2x-2

Step-by-step explanation:

once you plot the points, you see that the y-intercept is -2 and the rise over run is 6/3. you simplify 6/3 by dividing and get 2x. So y=2x-2.

Hope this helped!

7 0

3 years ago

An architect plans to buy 5 stone spheres and 3 stone cylinders. For the same amount, she can buy 2 stone spheres and 6 stone c

Vedmedyk [2.9K]

The cost of each stone sphere is $ 36.81

<em><u>Solution:</u></em>

Given that,

An architect plans to buy 5 stone spheres and 3 stone cylinders

For the same amount, she can buy 2 stone spheres and 6 stone cylinders

Let "x" be that same amount

Let "a" be the cost of each stone sphere

Cost of each stone cylinder = $ 36.81

Therefore,

x = 5 stone spheres and 3 stone cylinders

x = 5a + 3(36.81)

Similarly,

x = 2 stone spheres and 6 stone cylinders

x = 2a + 6(36.81)

Equate both,

$5a + 3(36.81) = 2a + 6(36.81)\\\\5a + 110.43 = 2a + 220.86\\\\5a - 2a = 220.86 - 110.43\\\\3a = 110.43\\\\a = 36.81$

Thus cost of each stone sphere is $ 36.81

7 0

3 years ago

Equiangular polygon has how many sides exterior angle is 25

Softa [21]

If the exterior angle is 25o then the interior angle is its supplement.
The interior angle = 180 - 25 = 155 degrees. All angles are equal in the interior.
The sides aren't.

I'm hoping you get an answer besides mine. I can take you so far.
The formula for an interior angle is

180(1 - 2/n) = Interior angle. When you solve this you get
180(1 - 2/n) = 155
1 - 2/n = 155/180
1 - 2/n = 0.86111111
- 2/n = 0.8611111 - 1
2/n = 0.13888888
2 / 0,1388888 = n
n = 14.4

You can google equiangular polygon theorem to see where I got the formula. The problem is that I really don't know how to interpret the answer. It looks like you have 14 conguent sides and 1 that is 0.4 left over. The figure might still be equiangular.

5 0

3 years ago