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3 years ago

can someone help me out with number 12 is this a function, and do it shows the value of domain, & range

Mathematics

1 answer:

Lerok [7]3 years ago

3 0

Domain: (-8, 2, 4) || set builder: {x = -8, 2, 4}

Range: (-6, -4, 12, 14) || set builder: {y = -6, -4, 12, 14}

This is not a function because the x-value (-8) is used twice. in a function, no two x-values can be the same

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Answer:

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Step-by-step explanation:

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3 years ago

Read 2 more answers

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Answer:

See below for answers and explanations

Step-by-step explanation:

Problem 4:

The line of regression is $\hat y = a+bx$ where:

$a=\overline y-b \overline x$

$b=\frac{r*s_y}{s_x}$

We are given that $\overline y=75$ , $s_y=8$ , $\overline x=280$ , $s_x=30$ , and $r=0.60$ , therefore our slope, $b$ , is:

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Therefore, the slope of the regression line is 0.16, which can be used along with the values of $\overline y$ and $\overline x$ to find the constant $a$ :

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This means our final regression line is $\hat y = 30.2 + 0.16x$

Problem 5:

The slope, $b=0.16$ , means that for every 1 point earned for a student's pre-exam total, their final exam score will increase by 0.16 points for each point they earned on the pre-exam.

Problem 6:

The y-intercept (or constant), $a=30.2$ , means that if a student's pre-exam total were 0, then they would expect to get a 30.2 on the final exam.

Problem 7:

$R^{2}=(0.60)^{2}=0.36=36\%$

Problem 8:

The fraction of variability (aka. coefficient of determination), $R^2$ , means that a certain proportion (or percentage) of the variance in the response variable can be explained by the explanatory variable. In context, this means that 36% of the variance in final exam scores can be explained by the pre-exam scores.

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3 years ago

Can you help me find a? 0.64 = a^2

erma4kov [3.2K]

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4 years ago

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64 divided by 4=16

144 divided by 9=16

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4 years ago

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slavikrds [6]

Answer:

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Step-by-step explanation:

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