If 3x-13=8, find the value of -4?

You can see that from ABC to A'B'C', it's rotated a positive 90 degrees. then, from A'B'C' to A"B"C", reflected across x-axis. and when writing the transformation, it goes by last to first. that's why the R 90 comes first.

8 0

3 years ago

In a lab, a substance was cooked by 42 C over a period of 7 hours at a constant rate. What was the change in temperature each ho

Mekhanik [1.2K]

Given that we have the change in temperature over 7 hours and we are looking for the change over 1 hour, we can divide the total change in temperature by 7. Thus, the change in temperature would be $\frac{42}{7} C^{\circ}$ .

Additionally, this can be solved by equations:

$\dfrac{42 \,\textrm{C}^{\circ}}{7 \,\textrm{hours}} = \dfrac{x \,\textrm{C}^{\circ}}{1 \,\textrm{hour}}$

$1 \,\textrm{hour} \cdot \dfrac{42 \,\textrm{C}^{\circ}}{7 \,\textrm{hours}} = x \,\textrm{C}^{\circ}$

$\dfrac{42}{7} \,\textrm{C}^{\circ} = x \,\textrm{C}^{\circ}$

$\dfrac{42}{7} = x$

By using two different methods, we can determine that the change each hour was equal to 42/7 C° per hour.

6 0

3 years ago

A machine that fills beverage cans is supposed to put 12 ounces of beverage in each can. The standard deviation of the amount in

erica [24]

Answer:

$\chi^2 =\frac{10-1}{0.0144} 0.0217 =13.54$

The degrees of freedom are:

$df=n-1=10-1=9$

Now we can calculate the p value using the alternative hypothesis:

$p_v =2*P(\chi^2 >13.54)=0.279$

Since the p value is higher than the signficance level assumed of 0.05 we have enough evidence to FAIL to reject the null hypothesis and there is no evidence to conclude that the true deviation differs from 0.12 ounces

Step-by-step explanation:

Assuming the following data:"12.14 12.05 12.27 11.89 12.06

12.14 12.05 12.38 11.92 12.14"

We can calculate the sample deviation with this formula:

$s =\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$n=10$ represent the sample size

$\alpha=0.05$ represent the confidence level

$s^2 =0.0217$ represent the sample variance

$\sigma^2_0 =0.12^2= 0.0144$ represent the value to verify

Null and alternative hypothesis

We want to determine whether the standard deviation differs from 0.12 ounce, so the system of hypothesis would be:

Null Hypothesis: $\sigma^2 = 0.0144$

Alternative hypothesis: $\sigma^2 \neq 0.0144$

The statistic can be calculated like this;

$\chi^2 =\frac{n-1}{\sigma^2_0} s^2$

$\chi^2 =\frac{10-1}{0.0144} 0.0217 =13.54$

The degrees of freedom are:

$df=n-1=10-1=9$

Now we can calculate the p value using the alternative hypothesis:

$p_v =2*P(\chi^2 >13.54)=0.279$

Since the p value is higher than the signficance level assumed of 0.05 we have enough evidence to FAIL to reject the null hypothesis and there is no evidence to conclude that the true deviation differs from 0.12 ounces

7 0

3 years ago