(2x - 5) (x^2 + x

ΔABC has three sides with these lengths: AB = 9, BC = 40, and CA = 41. What is the value of cos C?

kotykmax [81]

Answer:

$cos(C) =\frac{40}{41}\\\\cos(C)=0.976$

Step-by-step explanation:

To find the $cos (C)$ we must use the cosine theorem.

The cosine theorem says that:

$c^2 = a^2 +b^2 -2abcos(C)$

In this case:

$c=AB = 9$

$b=CA = 41$

$a=BC = 40$

So

$9^2 = 40^2 +41^2 -2(40)*(41)cos(C)$

$9^2- 40^2- 41^2 =-2(40)*(41)cos(C)$

$cos(C) = -\frac{9^2- 40^2- 41^2}{2(40)*(41)}$

$cos(C) =\frac{40}{41}\\\\cos(C)=0.976$

7 0

3 years ago

Help ASAP!! I need this done because im behind

Alenkasestr [34]

When you take any polynomial and subtract any other polynomial from it you always get a third polynomial that is the closure property

3 0

3 years ago

Which of the following is an arithmetic sequence?

pickupchik [31]

Find the difference between consecutive terms. If all of them in the sequence have the same difference, then it's an arithmetic sequence. The fourth answer, for example, is not an arithmetic sequence. The difference of 14 and 4 is 10 since 14-4=10. The difference of 24 and 14 is also 10. But the difference between 32 and 24 is 8. Since 8 isn't the same as the other differences, it's not an arithmetic sequence. That should be enough for you to determine which of the remaining sequences is arithmetic.

5 0

4 years ago

Read 2 more answers

In the figure shown, which composition of rigid motions will map one triangle onto the other?

Aloiza [94]

Answer: D. a rotation followed by a translation

7 0

3 years ago

According to a recent study of 7335 young people in the US, 30% had been arrested for a crime other than a traffic violation by

victus00 [196]

Answer:

a) Statistic.

b) The population proportion is expected to be between 0.29 and 0.31 with a 94% degree of confidence.

Step-by-step explanation:

a) The proportion of 30% is a statistic, as it is a value that summarizes data only from the sample taken in the study from USA Today. Other samples may yield different proportions.

b) We can use the statistic to estimate a confidence interval for the parameter of the population.

The standard error for the proportion is calculated as:

$\sigma_p=\sqrt{\dfrac{p(1-p)}{N}}=\sqrt{\dfrac{0.3\cdot 0.7}{7335}}=\sqrt{2.83\cdot10^5}= 0.00535$

The margin of error is 0.01. We can use this value to determine the level of confidence that represents.

The formula for the margin of error is:

$E=z\cdot \sigma_p=0.01\\\\z\cdot 0.0535=0.01\\\\z=1.87$

This z-value, according to the the standard normal distribution, corresponds to a confidence interval of 94%.

The interval for this margin of error is:

$p-E\leq \pi \leq p+E\\\\0.30-0.01\leq \pi \leq 0.30+0.01\\\\0.29\leq \pi \leq 0.31$

Then, we can conclude that the population proportion is expected to be between 0.29 and 0.31 with a 94% degree of confidence.

3 0

4 years ago

(2x - 5) (x^2 + x - 2) =