Write the equation in slope-intercept form show all your work 3x + 7 = 9

ohaa [14]

Answer:

$9\, w^{2} - 100 = (3\, w - 10) \, (3\, w + 10)$ .

Step-by-step explanation:

Fact:

$\begin{aligned} & (a - b)\, (a + b)\\ =\; & a^{2} + a\, b - a\, b - b^{2} \\ =\; & a^{2} - b^{2} \end{aligned}$ .

In other words, $(a^{2} - b^{2})$ , the difference of two squares in the form $a^{2}$ and $b^{2}$ , could be factorized into $(a - b)\, (a + b)$ .

In this question, the expression $(9\, w^{2} - 100)$ is the difference between two terms: $9\, w^{2}$ and $100$ .

$9\, w^{2}$ is the square of $3\, w$ . That is: $(3\, w)^{2} = 9\, w^{2}$ .
On the other hand, $10^{2} = 100$ .

Hence:

$9\, w^{2} - 100 = (3\, w)^{2} - (10)^{2}$ .

Apply the fact that $a^{2} - b^{2} = (a - b) \, (a + b)$ to factorize this expression. (In this case, $a = 3\, w$ whereas $b = 10$ .)

$\begin{aligned}& 9\, w^{2} - 100 \\ =\; & (3\, w)^{2} - (10)^{2} \\ = \; & (3\, w - 10)\, (3\, w + 10)\end{aligned}$ .

8 0

2 years ago

In a completely randomized experimental design, three brands of paper towels were tested for their ability to absorb water. Equa

arlik [135]

Answer:

Yes. At this significance level, there is evidence to support the claim that there is a difference in the ability of the brands to absorb water.

Step-by-step explanation:

The question is incomplete:

The significance level is 0.05.

The data is:

Brand X: 91, 100, 88, 89

Brand Y: 99, 96, 94, 99

Brand Z: 83, 88, 89, 76

We have to check if there is a significant difference between the absorbency rating of each brand.

Null hypothesis: all means are equal

$H_0:\mu_x=\mu_y=\mu_z$

Alternative hypothesis: the means are not equal

$H_a: \mu_x\neq\mu_y\neq\mu_z$

We have to apply a one-way ANOVA

We start by calculating the standard deviation for each brand:

$s_x^2=30,\,\,s_y^2=6,\,\,s_z^2=35.33$

Then, we calculate the mean standard error (MSE):

$MSE=(\sum s_i^2)/a=(30+6+35.33)/3=71.33/3=23.78$

Now, we calculate the mean square between (MSB), but we previously have to know the sample means and the mean of the sample means:

$M_x=92,\,\,M_y=97,\,\,M_z=84\\\\M=(92+97+84)/3=91$

The MSB is then:

$s^2=\dfrac{\sum(M_i-M)^2}{N-1}\\\\\\s^2=\dfrac{(92-91)^2+(97-91)^2+(84-91)^2}{3-1}\\\\\\s^2=\dfrac{1+36+49}{2}=\dfrac{86}{2}=43\\\\\\\\MSB=ns^2=4*43=172$

Now we calculate the F statistic as:

$F=MSB/MSE=172/23.78=7.23$

The degrees of freedom of the numerator are:

$dfn=a-1=3-1=2$

The degrees of freedom of the denominator are:

$dfd=N-a=3*4-3=12-3=9$

The P-value of F=7.23, dfn=2 and dfd=9 is:

$P-value=P(F>7.23)=0.01342$

As the P-value (0.013) is smaller than the significance level (0.05), the null hypothesis is rejected.

There is evidence to support the claim that there is a difference in the ability of the brands to absorb water.

3 0

3 years ago

What’s the answer for the formula question

Luda [366]

Answer: N = 5

Step-by-step explanation:

M = 3N + 4R

M = 43

R = 7

Replacing by the values

43 = 3N + 4*7

43 = 3N + 28

43-28 = 3N

3N = 15

N = 15/3

N = 5

5 0

3 years ago

How do you solve 6(2/3x-3)>3

VARVARA [1.3K]

Answer:

14>3

Step-by-step explanation:

you would need to turn the 3 in the parenthesis into a fraction which would result in 9/3. 2/3 - 9/3= -7/3

Multiply the 7/3 by 6 and by what I have always been taught, you only multiply the top of the fraction. This would leave it to be 42/3 which would be known as 14.

So therefore the answer would be 14>3

4 0

3 years ago

Allison is working two summer jobs, making $12 per hour lifeguarding and $8 per hour washing cars. Last week Allison worked 3 mo

timama [110]

Answer:

Allison worked 6 hours lifeguarding and 3 hours washing cars.

Step-by-step explanation:

Let

Number of hours Allison worked lifeguarding last week = x

Number of hours Allison worked washing cars last week = y

1. Last week Allison worked 3 more hours lifeguarding than hours washing cars hours, then

$x-y=3$

Lifeguarding:

$12 per hour

$12x in x hours.

Washing cars:

$8 pere hour

$8y in y hours.

2. Allison earned a total of $96, hence

$12x+8y=96$

You get the system of two equations:

$\left\{\begin{array}{l}x-y=3\\ \\12x+8y=96\end{array}\right.$

Plot the graphs of these two equations (see attached diagram). These line intersect at point (6,3), so Allison worked 6 hours lifeguarding and 3 hours washing cars.

3 0

3 years ago