Solving by the substitution method<br> y=3x+7<br> y-5x+8

Help me please!!!!!!!

Sav [38]

Answer:

- sign between 9 and 64 under root, it should be + sign

Step-by-step explanation:

(-4)*(-8)(2)= 64

It should read x= √9+64 but not √9-54 which lead to incorrect solution

3 0

4 years ago

Sammy's Sandwich Shop has a mean delivery time of 25 minutes with a standard deviation of 2 minutes. Determine the z-score for t

Jlenok [28]

Answer:the z score is - 1

Step-by-step explanation:

Assuming a normal distribution for the delivery time of sandwiches by Sammy's Sandwich Shop. We would apply the formula for normal distribution which is expressed as

z = (x - u)/s

Where

x = delivery times

u = mean delivery time

s = standard deviation

From the information given,

u = 25 minutes

s = 2 minutes

We want to determine the z-score for the number of sandwiches delivered in less than 23 minutes. It becomes

z = (23 - 25)/2 = - 1

7 0

3 years ago

Consider a value to be significantly low if its z score less than or equal to minus−2 or consider a value to be significantly hi

ziro4ka [17]

Answer:

If the weight is higher than 5.8886 gr would be considered significantly high

If the weight is lower than 5.6121 gr would be considered significantly low

Step-by-step explanation:

Previous concepts

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".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the weights of a population, and for this case we know the distribution for X is given by:

$X \sim N(5.75241,0.06281)$

Where $\mu=5.75241$ and $\sigma=0.06281$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

For the case when z =-2 we can do this:

$-2 = \frac{X-5.75241}{0.06281}$

And if we solve for X we got:

$X = 5.75241 -2*0.06281 =5.6121$

And for the other case when Z=2 we have:

$2 = \frac{X-5.75241}{0.06281}$

And if we solve for X we got:

$X = 5.75241 +2*0.06281 =5.8886$

If the weight is higher than 5.8886 gr would be considered significantly high

If the weight is lower than 5.6121 gr would be considered significantly low

5 0

3 years ago

What is the result of adding -2.9a t 6.8 and 4.4a - 7.3 if a=2 what is the value of the expression

oksian1 [2.3K]

Answer:

Step-by-step explanation:

2.5

3 0

3 years ago

Why can you use Linear Pairs and Vertical Angles to prove lines are parallel?

natta225 [31]

Answer:

The reason why linear pairs and vertical angles are used to prove lines are parallel is because they area transversal drawn through the parallel lines will form angles on each of the two parallel lines including;

1) Supplementary linear pairs and

2) Vertical angles

3) Alternate angles

Given that either;

a) The corresponding angles that form the linear pairs are congruent

b) The corresponding vertically opposite angles are congruent

c) The corresponding alternate angles are congruent, we have;

The two lines are said to be parallel.

Step-by-step explanation:

5 0

3 years ago

Solving by the substitution method y=3x+7 y-5x+8