Which pair of ratios form a proportion?a. 9/23 and 27/46 b. 11/6 and 44/36 c. 13/4 and 65/24 d. 19/14 and 57/42

Which ordered pair is a reflection of (3, 7) across the y-axis?

worty [1.4K]

Answer:

(-3, 7)

Step-by-step explanation:

It is like putting a mirror on the y-axis. It is asking what point is the photo negative of the point, like a mirror. You see yourself in the mirror but everything is opposite. Your right hand is your left. So which point is the photo negative of (3, 7)? (-3, 7) Because it is only across the y-axis, the y value stays the same.

3 0

2 years ago

HELP PLEASEE no links hellpp

bezimeni [28]

Answer:

B and E

Step-by-step explanation:

perpendicular sides mean they will equal 90 degrees... so all rectangles and squares are perpendicular- a 90 degree triangle also is perpendicular. The Equatorial and the Acute triangle do not have 90 degree angles

4 0

3 years ago

At the beach this weekend, the ratio of sandcastles to kites was 3 to 5. If there were 15 kites spotted, how many items were see

Gelneren [198K]

Answer: 24

Step-by-step explanation:

The ratio of sandcastles to kites was 3 to 5 so if 15 kites were spotted that meant that the 5 was multiplied by 3 so then we multiply the 3 by 3. Now there are 9 sandcastles and 15 kites so now we add 9 to 15 to figure out how many items were seen in all. Nine added to 15 equals 24 which means that 24 items were seen in total.

6 0

3 years ago

can someone please help me find the surface area of the pyramid with an equilateral triangle for a base

ioda

To obtain the total surface we have to calculate the surface of the 4 triangles and add up the areas (remember that the area of a triangle is (b*h)/2 , b is the base, h is the height ).

We will caculate first the area of the base triangle for that we considerer the fact that it is an equilateral triangle with sides of lenght 6 cm, now we calculate the height, I am going to draw please wait a moment

using the pythagorean theorem we have that

$\begin{gathered} h^2=6^2cm^2-3^2\operatorname{cm}=27cm^2 \\ h=\text{ }\sqrt[]{27\text{ }}cm \end{gathered}$

Then, the area of the triangle is 6*h/2 = 3h = 15.59 cm^2.

Now we calculate the area of the other 3 triangles, notice that those triangles have the same base and height so we will calculate for one of them and multiply by 3. From the image we know that the height is 15cm and the base is 6 cm so the area is 45cm^2, and 45*3 cm^2 = 135cm^2.

Finally we add up all the areas:

$135cm^2+15.59cm^2=150.59cm^2$

6 0

1 year ago

in the unted states, the height of men are normally distributed with the mean 69 inches and standard deviation 2.8 inches. If 16

yaroslaw [1]

Answer:

Probability that their mean height is less than 68 inches is 0.0764.

Step-by-step explanation:

We are given that in the united states, the height of men are normally distributed with the mean 69 inches and standard deviation 2.8 inches.

Also, 16 men are randomly selected.

Let $\bar X$ = sample mean height

The z-score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean height = 69 inches

$\sigma$ = population standard deviation = 2.8 inches

n = sample of men = 16

The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.

So, probability that the mean height of 16 randomly selected men is less than 68 inches is given by = P( $\bar X$ < 68 inches)

P( $\bar X$ < 68 inches) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ < $\frac{68-69}{\frac{2.8}{\sqrt{16} } }$ ) = P(Z < -1.43) = 1 - P(Z $\leq$ 1.43)

= 1 - 0.9236 = 0.0764

Now, in the z table the P(Z x) or P(Z < x) is given. So, the above probability is calculated by looking at the value of x = 1.43 in the z table which has an area of 0.92364.

Therefore, probability that their mean height is less than 68 inches is 0.0764.

3 0

4 years ago