Please help me answer 19 and 20 show work

Rewrite in simplest terms: (9x+5)-(-2x+10)(9x+5)−(−2x+10)

Blababa [14]

$\implies {\blue {\boxed {\boxed {\purple {\sf { 18 {x}^{2} - 69x - 55}}}}}}$

$\large\mathfrak{{\pmb{\underline{\orange{Step-by-step\:explanation}}{\orange{:}}}}}$

$= (9x + 5) - ( - 2 x+ 10)(9x + 5) - ( - 2x + 10)$

$= (9x + 5) + 2x (9x + 5) - 10(9x + 5) - ( - 2x + 10)$

$= 9x + 5 + 18 {x}^{2} + 10 x- 90x - 50 + 2x - 10$

Collect the like terms.

$= 18 {x}^{2} + (9x + 10x- 90x + 2x) + (5 - 50 - 10)$

$= 18 {x}^{2} + (21x - 90x) +(5 - 60)$

$= 18 {x}^{2} - 69x - 55$

<h3> $\boxed{ Note:}$ </h3>

$\sf\pink{PEMDAS\: rule.}$

P = Parentheses

E = Exponents

M = Multiplication

D = Division

A = Addition

S = Subtraction

$\red{\large\qquad \qquad \underline{ \pmb{{ \mathbb{ \maltese \: \: Mystique35♛}}}}}$

3 0

3 years ago

Is the following relation a function?<br><br>O Yes <br>O No

posledela

No its not a function

3 0

3 years ago

PLEASE HELP!

11111nata11111 [884]

Answer:

B. Area = 256pi & Circumference = 32pi

Step-by-step explanation:

Area = pi r^2

A = pi (16)^2

A = 256pi

Circumference = 2pi r

C = 2(pi)(16)

C = 32pi

5 0

3 years ago

Five students received the same message at 9am. Each of them sent the message to 5 more students at 10 am. How many got the mess

Natali5045456 [20]

5 received at 9 am

then each sent the message to 5 more students

5*5 = 25

5+25 = 30 students got the message

3 0

4 years ago

A researcher reports survey results by stating that the standard error of the mean is 25 the population standard deviation is 40

bezimeni [28]

Answer:

a) A sample of 256 was used in this survey.

b) 45.14% probability that the point estimate was within ±15 of the population mean

Step-by-step explanation:

This question is solved using the normal probability distribution and the central limit theorem.

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .