What value for c will make the expression a perfect square trinomial?

These work problems are always done in terms of fractions ie if both (Kevin & Eric) took 30mins to mow and Kevin took 1.5hrs (90mins) alone then we can make an equation like below

1/time took for both = 1/time took for Kevin + 1/time took for Eric

1/30 = 1/90+1/x ==> calling time took for Kevin x

solving the above 1/x = 1/30-1/90

1/x=2/90

x=45

6 0

3 years ago

A statistics teacher taught a large introductory statistics class, with 500 students having enrolled over many years. The mean s

soldi70 [24.7K]

Answer:

The teacher select a sample of n =15 students. And he wanted to know if teaching a smaller class was more effective and students performed better, that means if $\mu >78$ and he obtaind a sample mean of $\bar X>83$ .

Based on this the correct system of hypothesis are:

Null hypothesis: $\mu =78$

Alternative hypothesis: $\mu >78$

And the best option for this case is:

a. H0: $\mu=78$ vs. H1: $\mu>78$ .

Step-by-step explanation:

For this case we have the following previous info given:

$\mu = 78$ represent the true mean

$\sigma =10$ represent the true deviation

The teacher select a sample of n =15 students. And he wanted to know if teaching a smaller class was more effective and students performed better, that means if $\mu >78$ and he obtaind a sample mean of $\bar X>83$ .

Based on this the correct system of hypothesis are:

Null hypothesis: $\mu =78$

Alternative hypothesis: $\mu >78$

And the best option for this case is:

a. H0: $\mu=78$ vs. H1: $\mu>78$ .

5 0

3 years ago

Help pretty please and thank you

belka [17]

9514 1404 393

Answer:

0.404 . . . cm/day
the average growth per day in cm

Step-by-step explanation:

The slope is the x-coefficient in the equation, 0.404.

The slope is the rate of change of the dependent variable (height) with respect to the independent variable (number of days). In this case, it is the average increase in the plant's height each day, in cm.

5 0

3 years ago