Terrence would like to estimate the mean the number of books students at his school read during the summer. There are 595 students at his school. Which statements are true?

Select each correct answer.

To estimate the mean using a sample, Terrance will need to randomly select the students he will survey so that the sample represents the population well.

The mean can only be estimated by surveying all 595 students.

The larger the number of students Terrance surveys, the better his estimate of the mean will be.

If Terrance collects a sample of students in the library reading, and surveys them, he can use that data to estimate the mean of the number of books read by all students.

1. perpendicular

2. parallel

3. perpendicular

-8/2y-8=5/y+4-7y+8/y^2-16

we move all terms to the left:

-8/2y-8-(5/y+4-7y+8/y^2-16)=0

we can not solve this equation

the value of x is 9 ⇒ answer b

step-by-step explanation:

* we can solve this problem using cosine and sine rule

- in δ abc

∵ ab = 36 , bc = 28 , ac = 16

- lets find the measure of angle b using the cosine rule

∵ cos b = [ab² + bc² - ac²]/2(ab)(bc)

∴ cos b = [36² + 28² - 16²]/2(36)(28)

∴ cos b = 19/21

∴ m∠b = cos^-1(19/21) ≅ 25°

- lets find the measure of angle a using the sine rule

∵ sina/bc = sinb/ac = sinc/ab

∴ sina/28 = sin25°/16 ⇒ by using cross multiplication

∴ sina = 28 × sin25°/16

∴ sina = 0.7396

∴ m∠a = sin^-1(0.7396) ≅ 48°

- from the figure m∠abd = m∠dbc

∵ m∠abc = 25°

∴ m∠abd = 25°/2 = 12.5°

- in δabd

∵ m∠a = 48° , m∠abd = 12.5°

∵ the sum of the measures of the interior angles of any δ is 180°

∴ m∠adb = 180° - (48° + 12.5°) = 119.5°

∵ ab = 36

∵ ad = x

- use the sine rule to find x

∵ sin∠adb/ab = sin∠abd/x

∴ sin119.5°/36 = sin12.5°/x ⇒ by using cross multiplication

∴ x = 36 × sin12.5°/sin119.5° = 8.95 ≅ 9

* the value of x is 9

we need to see the graph to know but

strong positive is if it is going up from left to right in a straight diagonal line (like this /)

strong negative is the same but from right to left (like this \)

weak negative is the same as strong negative but its more straight line still right to left

and weak positive is the same as strong positive but more a straight line still left to right though.