Find the non permissible replacement for y+3/y-1

Find the distance between the lines with equations -4x + 7y + 9 = 0 and y = 4/7x - 9

kiruha [24]

It’s 6.72 you add the two numbers

5 0

4 years ago

Can u solve it?<br> Find x,y,v and u.

ikadub [295]

Explanation:

Basically, you can do it in many ways. But just, in my opinion, exactly linear algebra was made for such cases.

the optimal way is to do it with Cramer's rule.

First, find the determinant and then find the determinant x, y, v, u.

Afterward, simply divide the determinant of variables by the usual determinant.

eg. $\frac{Dx_{} }{D}$ and etc.

I think that is the best way to solve it without a hustle of myriad of calculations reducing it to row echelon form and solving with Gaussian elimination.

5 0

2 years ago

Many, many snails have a one-mile race, and the time it takes for them to finish is approximately normally distributed with mean

Mamont248 [21]

Answer:

a) The percentage of snails that take more than 60 hours to finish is 4.75%.

b) The relative frequency of snails that take less than 60 hours to finish is 95.25%.

c) The proportion of snails that take between 60 and 67 hours to finish is 4.52%.

d) 0% probability that a randomly-chosen snail will take more than 76 hours to finish

e) To be among the 10% fastest snails, a snail must finish in at most 42.32 hours.

f) The most typical 80% of snails take between 42.32 and 57.68 hours to finish.

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:

$\mu = 50, \sigma = 6$

a. The percentage of snails that take more than 60 hours to finish is

This is 1 subtracted by the pvalue of Z when X = 60.

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

$Z = \frac{60 - 50}{6}$

$Z = 1.67$

$Z = 1.67$ has a pvalue 0.9525

1 - 0.9525 = 0.0475

The percentage of snails that take more than 60 hours to finish is 4.75%.

b. The relative frequency of snails that take less than 60 hours to finish is

This is the pvalue of Z when X = 60.

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

$Z = \frac{60 - 50}{6}$

$Z = 1.67$

$Z = 1.67$ has a pvalue 0.9525

The relative frequency of snails that take less than 60 hours to finish is 95.25%.

c. The proportion of snails that take between 60 and 67 hours to finish is

This is the pvalue of Z when X = 67 subtracted by the pvalue of Z when X = 60.

X = 67

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

$Z = \frac{67 - 50}{6}$

$Z = 2.83$

$Z = 2.83$ has a pvalue 0.9977

X = 60

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

$Z = \frac{60 - 50}{6}$

$Z = 1.67$

$Z = 1.67$ has a pvalue 0.9525

0.9977 - 0.9525 = 0.0452

The proportion of snails that take between 60 and 67 hours to finish is 4.52%.

d. The probability that a randomly-chosen snail will take more than 76 hours to finish (to four decimal places)

This is 1 subtracted by the pvalue of Z when X = 76.

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

$Z = \frac{76 - 50}{6}$

$Z = 4.33$

$Z = 4.33$ has a pvalue of 1

1 - 1 = 0

0% probability that a randomly-chosen snail will take more than 76 hours to finish

e. To be among the 10% fastest snails, a snail must finish in at most hours.

At most the 10th percentile, which is the value of X when Z has a pvalue of 0.1. So it is X when Z = -1.28.

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

$-1.28 = \frac{X - 50}{6}$

$X - 50 = -1.28*6$

$X = 42.32$

To be among the 10% fastest snails, a snail must finish in at most 42.32 hours.

f. The most typical 80% of snails take between and hours to finish.

From the 50 - 80/2 = 10th percentile to the 50 + 80/2 = 90th percentile.

10th percentile

value of X when Z has a pvalue of 0.1. So X when Z = -1.28.

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

$-1.28 = \frac{X - 50}{6}$

$X - 50 = -1.28*6$

$X = 42.32$

90th percentile.

value of X when Z has a pvalue of 0.9. So X when Z = 1.28

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

$1.28 = \frac{X - 50}{6}$

$X - 50 = 1.28*6$

$X = 57.68$

The most typical 80% of snails take between 42.32 and 57.68 hours to finish.

5 0

4 years ago

M Find the measure of the angles.

bearhunter [10]

Answer:

Since the interior angles of a triangle add up to be 180 degrees, I set up the equation like so:

x + 59 + x + 51 + 84 = 180 My equation

2x + 194 = 180 add like terms

2x = -19 subtract 194 from both sides of the equation

x = -7 divided both by 2x to get x alone

It has occurred to me that I am finding x here (it still makes no sense to get a negative number) but this is the only equation I know to set up.

Notes:

This is for geometry homework and I realize just asking you to solve my problems is academically dishonest off topic if I have not put genuine effort into the question, which I have (put effort in, that is). I have put a lot of mental effort into figuring this out, though, so I will tell you what I did and hopefully you can tell me where I went wrong and how to correct my mistake, because I think it is obvious I made one. For the record I accidentally deleted my math notes from my iPad and Googling the question this morning produces hard to understand results. My geometry teacher was unavailable while I was working last night due to my lack of internet connection.

6 0

3 years ago

a line represented by y = 5x − 2 and a line perpendicular to it intersect at r(1, 3). what is the equation of the perpendicular

Snezhnost [94]

Y=ax+b, y=cx+d (a≠0, c≠0)
If the two line cross perpendicularly ⇔ ac= -1

So a tangent of the perpendicular line is "-(1/5)".

Then, the equation of the perpendicular line is y=-(1/5)x+a (a is <span> y-intercept</span>).

On the other hand, this equation pass r(1, 3), so

3 = -(1/5) times 1 + a

∴ a=16 / 5

Therefore, y=-(1/5)x+16 /5 is answer.

By the way, I'm Japanese so if you find some mistakes in my English, please let me know.

5 0

4 years ago