All categories

2 years ago

Solve each system by elimination 9x - 6y = -21 and -9x + 9y = 18

Mathematics

2 answers:

IrinaK [193]2 years ago

7 0

Answer:

X= -3, Y= -1

Step-by-step explanation:

loris [4]2 years ago

6 0

<h2>Answer</h2>

= {x, y}

= {-1.-3}

X = -1

Y = -3

<h2>Explain</h2>

Look at the picture :)

#LearnWithBrainly

<h3>gak bisa bahasa inggris</h3>

You might be interested in

Warren wants to build a rectangular enclosure for his animals. one side of the pen will be against the barn, so he needs no fenc

Lera25 [3.4K]

L +2w = 500
a = lw

a) l = 500 -2w
.. a = (500 -2w)*w

b) The zeros of the above equation are w=0, w=250. The vertex of this quadratic is on the line of symmetry, halftway between the zeros, at w=125 ft.

c) a = (500 -2*125)*125 = 31,250 . . . . square feet

7 0

2 years ago

How many whole-number solutions does the inequality |x-5|≤8 have?

-BARSIC- [3]

The answer is -3 to 13

6 0

2 years ago

You don’t know how important this is Please help me!!

Natali5045456 [20]

Answer:

f(x)= $\frac{7}{5}$ x- $\frac{6}{5}$

Step-by-step explanation:

First put 7x-5y=6 into slope intercept form

y= $\frac{7}{5}$ x- $\frac{6}{5}$

Then put it into f(x) form

7 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:

<em>The question is incomplete:</em>

<em>The significance level is 0.05.</em>

<em>Brand X: 91, 100, 88, 89</em>

<em>Brand Y: 99, 96, 94, 99</em>

<em>Brand Z: 83, 88, 89, 76</em>

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

Are these correct? Please help with #12

BartSMP [9]

All of them seem pretty correct.
Also the answer to 12 is this...

Remove unnecessary parentheses
-6x2/3p^8x3

Then reduce the #’s with the greatest common divisor 3

-6x2p^8

Calculate the product

-12p^8

And that’s your answer:)))

8 0

3 years ago