Graph the inequality. 0

Homework, 12 points for whoever answers.

adell [148]

The answer to number 1 = 40

5 0

2 years ago

Read 2 more answers

How to reflect over y axis in an equation?

iren [92.7K]

1) y = -f(x) (This is the reflection about the x-axis of the graph y = f(x).) That is for every point (x, y) there is a point (x, -y).
2) y = |f(x)| means that the entire graph will be above the x-axis. Why? (The absolute value is always positive, that's why!!) To graph the absolute value graph, graph the function y = f(x). Anything above the x-axis, stays above it, anything below the x-axis is reflected above the x-axis and anything on the x-axis, stays on the x-axis.
3) y = f(-x) (This is reflection about the y-axis of the graph y = f(x)) For every point on the right of the y-axis, there is a point equidistant to the left of the y-axis. That is for every point (x, y), there is a point (-x, y).
4) Reflections about the line y = x is accomplished by interchanging the x and the y-values. Thus for y = f(x) the reflection about the line y = x is accomplished by x = f(y). Thus the reflection about the line y = x for y = x2 is the equation x = y2.

7 0

2 years ago

Two catalysts may be used in a batch chemical process. Twelve batches were prepared using catalyst 1, resulting in an average yi

aalyn [17]

Answer:

a) $t=\frac{(91-85)-(0)}{2.490\sqrt{\frac{1}{12}}+\frac{1}{15}}=6.222$

$df=12+15-2=25$

$p_v =P(t_{25}>6.222) =8.26x10^{-7}$

So with the p value obtained and using the significance level given $\alpha=0.01$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis.

b) $(91-85) -2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =3.309$

$(91-85) +2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =8.691$

Step-by-step explanation:

Notation and hypothesis

When we have two independent samples from two normal distributions with equal variances we are assuming that

$\sigma^2_1 =\sigma^2_2 =\sigma^2$

And the statistic is given by this formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{S_p\sqrt{\frac{1}{n_1}}+\frac{1}{n_2}}$

Where t follows a t distribution with $n_1+n_2 -2$ degrees of freedom and the pooled variance $S^2_p$ is given by this formula:

$\S^2_p =\frac{(n_1-1)S^2_1 +(n_2 -1)S^2_2}{n_1 +n_2 -2}$

This last one is an unbiased estimator of the common variance $\sigma^2$

Part a

The system of hypothesis on this case are:

Null hypothesis: $\mu_2 \leq \mu_1$

Alternative hypothesis: $\mu_2 > \mu_1$

Or equivalently:

Null hypothesis: $\mu_2 - \mu_1 \leq 0$

Alternative hypothesis: $\mu_2 -\mu_1 > 0$

Our notation on this case :

$n_1 =12$ represent the sample size for group 1

$n_2 =15$ represent the sample size for group 2

$\bar X_1 =85$ represent the sample mean for the group 1

$\bar X_2 =91$ represent the sample mean for the group 2

$s_1=3$ represent the sample standard deviation for group 1

$s_2=2$ represent the sample standard deviation for group 2

First we can begin finding the pooled variance:

$\S^2_p =\frac{(12-1)(3)^2 +(15 -1)(2)^2}{12 +15 -2}=6.2$

And the deviation would be just the square root of the variance:

$S_p=2.490$

Calculate the statistic

And now we can calculate the statistic:

$t=\frac{(91-85)-(0)}{2.490\sqrt{\frac{1}{12}}+\frac{1}{15}}=6.222$

Now we can calculate the degrees of freedom given by:

$df=12+15-2=25$

Calculate the p value

And now we can calculate the p value using the altenative hypothesis:

$p_v =P(t_{25}>6.222) =8.26x10^{-7}$

Conclusion

So with the p value obtained and using the significance level given $\alpha=0.01$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis.

Part b

For this case the confidence interval is given by:

$(\bar X_1 -\bar X_2) \pm t_{\alpha/2} S_p \sqrt{\frac{1}{n_1} +\frac{1}{n_2}}$

For the 99% of confidence we have $\alpha=1-0.99 = 0.01$ and $\alpha/2 =0.005$ and the critical value with 25 degrees of freedom on the t distribution is $t_{\alpha/2}= 2.79$

And replacing we got:

$(91-85) -2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =3.309$

$(91-85) +2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =8.691$

7 0

2 years ago

Which value of y below is the solution to the system shown below. A) y=6 B) y=-1 C) y=-4 D) y=8

Grace [21]

Answer:

D

Step-by-step explanation:

given the 2 equations

x + 2y = 27 → (1)

2x + 3y = 46 → (2)

Rearrange (1) expressing x in terms of y by subtracting 2y from both sides

x = 27 - 2y ← substitute into (2)

2(27 - 2y) + 3y = 46

54 - 4y + 3y = 46

54 - y = 46 ( subtract 54 from both sides )

- y = - 8 ( multiply both sides by - 1 )

y = 8 → D

4 0

2 years ago

Plz help me

Iteru [2.4K]

Answer:

I think the answer is 60 feet.

Step-by-step explanation:

Because his rate is 2 feet per second and the question asks where he'll be after 30 seconds, the answer has to be 60 feet.

I hope this helps!

5 0

2 years ago

Graph the inequality. 0 < y + 4x <6