Statistic significance requires that your sample be representative of the population, but I'm struggling with this because if the class is an elective then the answer would be: <span>No, it is not a valid inference because she asked all 22 students in her science class instead of taking a sample of the students in her school.
BUT if the class is required, as most science classes are, then it WOULD be a random sample of the school. So the last option would be correct.
My guess though is that the teacher is looking for answer B.
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Answer:
the data that is shown represents a function
Step-by-step explanation:
the easiest way to know is by looking at the x-variable. Each y-variable needs one x-variable. the x-variable should not be seen paired with another y-variable.
Answer:
x=8, y = 0
Step-by-step explanation:
Substitution is easier for this problem.
3x + y = 24 ---> y = 24 - 3x
x^2 + y = 64
Substitute y
x^2 + 24 - 3x = 64
x^2 - 3x = 40
Factor out x
x(x-3) = 40
Pretty much you can guess and check
x = 8
If x = 8, y = 0
or
x^2 - 3x = 40
Complete the square
x^2 - 3x + 2.25 = 42.25
(x-1.5) ^2 = 42.25
Square root both sides
x - 1.5 = 6.5
x=8
x - 1.5 = -6.5
x = -5
Check
x = -5 doesn't work, so x = 8 and y = 0
Answer: 2.8 x 10^-3
Step-by-step explanation: Because 10^-3 moves the decimal backwards 3 times