Which expression is equivalent to the one shown below?

Assume that 0 < x < pi/2 0 < y < pi/2 Find the exact value of cos(x - y) * if * cos x = 3/5 and cos y = 4/5

jasenka [17]

Answer:C

Step-by-step explanation: It’s C because I guessed that $h1t and looked back and I got it right. When in doubt always pick C my dudes.

8 0

3 years ago

Insurance companies are interested in knowing the population percent of drivers who always buckle up before riding in a car. The

Tems11 [23]

Answer:

The 84% confidence interval for the population proportion that claim to always buckle up is (0.74, 0.80).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

They randomly survey 387 drivers and find that 298 claim to always buckle up.

This means that $n = 387, \pi = \frac{298}{387} = 0.77$

84% confidence level

So $\alpha = 0.16$ , z is the value of Z that has a p-value of $1 - \frac{0.16}{2} = 0.92$ , so $Z = 1.405$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.77 - 1.405\sqrt{\frac{0.77*0.23}{387}} = 0.74$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.77 + 1.405\sqrt{\frac{0.77*0.23}{387}} = 0.8$

The 84% confidence interval for the population proportion that claim to always buckle up is (0.74, 0.80).

6 0

3 years ago

Click the spot on the graph C' would-be located if the triangle was rotated 180 degrees clockwise

lara31 [8.8K]

Assuming that the figure is rotated about the origin, a rotation of 180° is described by the rule:

$(x,y)\rightarrow(-x,-y)$

The coordinates of the point <em>C</em> are (4,7). Then, after a rotation of 180°:

$(4,7)\rightarrow(-4,-7)$

Therefore, the coordinates of C' would be:

$(-4,-7)$

5 0

1 year ago

Giving your answer in the form of e, find (given in the picture)

Anuta_ua [19.1K]

Answer:

1 is the answer

if you like my answer please like comment and mark me as brilliant

3 0

2 years ago

HELP PLEASE find the x-intercepts of the parabola with vertex -1,-17 and y-intercept 0,-13. Write your answer in this form: (x1,

Rzqust [24]

Answer:

(1.06, 0), (-3.06, 0)

Step-by-step explanation:

Substitute the vertex (-1, -17) and the point (0, -13) into the vertex form of a parabola: y = a(x - h)^2 + k. Solve for a.

-13 = a(0 - (-1))^2 - 17

Simplify this equation.

-13 = a(1)^2 - 17

Evaluate the exponent.

-13 = a - 17

Add 17 to both sides.

4 = a

Now substitute the vertex and the a-value into the vertex form of a parabola: y = a(x - h)^2 + k.

y = 4(x - (-1))^2 - 17

Simplify.

y = 4(x + 1)^2 - 17

Now to find the x-intercepts, make y = 0.

4(x + 1)^2 - 17 = 0

Add 17 to both sides.

4(x + 1)^2 = 17

Square root both sides.

2(x + 1) = $\pm\sqrt{17}$

Divide both sides by 2.

x + 1 = $-1\pm\frac{\sqrt{17}}{2}$

Subtract 1 from both sides.

x = $\left \{ {{-1+\frac{\sqrt{17}}{2} ~= ~1.06} \atop {-1-\frac{\sqrt{17}}{2}~=~-3.06}} \right.$

Since you want the answers in the form (x1, y1), (x2, y2) and for the answers to be rounded to the nearest hundredth, your final answers are:

(1.06, 0), (-3.06, 0)

6 0

3 years ago