1.Eric earned a 12 correct points out of 15 total points on his math quiz.

damaskus [11]

(x,y) = (r,16)

With this knowledge, plug in r for x, and 16 for y

16 = 2(r) - 4

Isolate the r, add 4 to both sides

16 (+4) = 2r - 4 (+4)

20 = 2r

Divide 2 from both sides

20/2 = 2r/2

r = 20/2

r = 10

hope this helps

4 0

2 years ago

The base of a solid right pyramid is a regular hexagon with a radius of 2x units and an apothem of units. A solid right pyramid

Xelga [282]

Answer:

$6 x^2*\sqrt{3}$

Step-by-step explanation:

The base of the pyramid we need to study is a hexagon.

Let's look at the attached image of an hexagon to understand how we are going to find the area of this figure.

Notice that an hexagon is the combination of 6 exactly equal equilateral triangles in our case of size "2x" (notice that the "radius" of the hexagon is given as "2x")

Therefore the area of the hexagon is going to be 6 times the area of one of those equilateral triangles.

We know the area of a triangle is the product of its base times its height, divided by 2: $\frac{base*height}{2} = \frac{2x*height}{2}$

We notice that the triangle's height is exactly what is called the "apothem" of the hexagon (depicted in green in our figure) which measures $x\sqrt{3}$ , so replacing this value in the formula above for the area of one of the triangles:

$\frac{2x*height}{2}= \frac{2x*x\sqrt{3} }{2}=x^2\sqrt{3}$

Then we multiply this area times 6 to get the total area of the hexagon (6 of these triangles):

Area of hexagon = $6x^2\sqrt{3}$

which is the last option given in the list.

5 0

2 years ago

Read 2 more answers

What is an equation of the line that passes through the point (−3,−1) and is perpendicular to the line x-2y=6?

gogolik [260]

Answer:

y = 2x+5

Step-by-step explanation:

rearrange the equation to make y the sof

y = 1/2x - 3

to find gradient of perpendicular line

1/2 ÷ ( - 1 )

y = -2x + c , the replace the coordinates (-3,-1)

y = 2x + 5

5 0

2 years ago

A set of exam scores is normally distributed and has a mean of 80.2 and a standard deviation of 11. What is the probability that

ZanzabumX [31]

Answer:

93.32% probability that a randomly selected score will be greater than 63.7.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value 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. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 80.2, \sigma = 11$