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3 years ago

What set of reflections would carry triangle abc onto itself?

2 answers:

7 0

Since all reflections are inverse of itself, carrying any reflection about the same axis twice will carry the preimage back to itself.

shepuryov [24]3 years ago

3 0

Answer is y axis , x axis, y axis , x axis .

Let The triangle ABC is in first quadrant of a two dimensional graph where it is reflected by positive of y axis and it is reflected image will be in second quadrant ,there it is reflected by negative of x axis and the reflected image will be in third quadrant now, here it is reflected by negative of y axis and its reflected image will be in fourth quadrant ,finally it will reflected by positive of x axis and its reflected image will be back in first quadrant.

So the answer is y axis , x axis, y axis , x axis are the of reflections which would carry triangle onto itself.

You might be interested in

If nine times a certain number is subtracted from 7 the result is 52. Find the number.

mezya [45]

Answer:

Let the number to find be x

7 - 9x = 52

-9x = 52-7

- 9x = -45

Divide by - 9

x = 5

The number is 5

Hope this helps.

6 0

3 years ago

Read 2 more answers

If two straight lines intersect and one angle is 30 degrees what are the other three angles

mel-nik [20]

Easey peasy
oposite angle is equal
other angles are supplementary (supplementary means add to 180, and a straight line=180 so if you look at 2 lines intersecting and think for a little bit, you wiill see why)

oposite angle=30
other angle is adds to 180
30+other=180
subtract 30
other=150
other is oposite other other
other=other other
150=other other

angles are
150,30,150

3 0

2 years ago

Read 2 more answers

Find the equation of the circle with center at (-1, 3) and radius of 4.

Nataly [62]

Answer:

(x+1)^2 + (y-3)^2 = 16

Step-by-step explanation:

The equation of a circle is given by

(x-h)^2 + (y-k)^2 = r^2

Where (h,k) is the center and r is the radius

(x--1)^2 + (y-3)^2 = 4^2

(x+1)^2 + (y-3)^2 = 4^2

(x+1)^2 + (y-3)^2 = 16

7 0

2 years ago

GRE Test: The Graduate Record Examination (GRE) is a test required for admission to many US graduate schools. Student’s scores o

Zepler [3.9K]

Answer:

a) $\bar X=144.3$

b) The 95% confidence interval would be given by (138.846;149.754)

c) n=34

d) n=298

e) n=1190

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

We can calculate the sample mean with this formula:

$\bar X = \frac{\sum_{i=1}^n x_i}{n}$

$\bar X=144.3$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma=8.8$ represent the population standard deviation

n=10 represent the sample size

a) Find a point estimate of the population mean

We can calculate the sample mean with this formula:

$\bar X = \frac{\sum_{i=1}^n x_i}{n}$

$\bar X=144.3$

b) Construct a 95% confidence interval for the true mean score for this population.

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.025,0,1)".And we see that $t_{\alpha/2}=1.96$

Now we have everything in order to replace into formula (1):

$144.3-1.96\frac{8.8}{\sqrt{10}}=138.846$

$144.3+1.96\frac{8.8}{\sqrt{10}}=149.754$

So on this case the 95% confidence interval would be given by (138.846;149.754)

Part c

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (a)

And on this case we have that ME =+20 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (b)

The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got $z_{\alpha/2}=1.960$ , replacing into formula (5) we got:

$n=(\frac{1.960(8.8)}{3})^2 =33.05 \approx 34$

So the answer for this case would be n=34 rounded up to the nearest integer

Part d

$n=(\frac{1.960(8.8)}{1})^2 =297.493 \approx 298$

So the answer for this case would be n=298 rounded up to the nearest integer

Part e

$n=(\frac{1.960(8.8)}{0.5})^2 =1189.97 \approx 1190$

So the answer for this case would be n=1190 rounded up to the nearest integer

7 0

3 years ago

The length of a city block running north to south in NYC is about 5 times 10 to the negative second power miles. The distance fr

NemiM [27]

So nyc=5 times 10^-2 miles

NYC-Mumbai=7.5 times 10^3

so
5 times 10^-2 times x=7.5 times 10^3
divide both sdies by 5 times 10^-2
x=(7.5 times 10^3)/(5 times 10^-2)
when dividing scientific notation you do this
x=(7.5 times 10^3)/(5 times 10^-2)=(7.5/5) times ((10^3)/(10^-2))
to divide exponents just subtract top from bottom
3-(-2)=5
answer is
x=1.5 times 10^5

7 0

3 years ago