Answer:
22-9t
Step-by-step explanation:
(7 - 3t) + 3(-2t + 5)
=
7+−3t+(3)(−2t)+(3)(5)=
7+−3t+−6t+15
=
Now you need to combine like terms.
7+−3t+−6t+15
=
(−3t+−6t)+(7+15)=
-9t+22=
22-9t
There you go.
I remember some of this from 6th grade!
a.) the 7th graders have a smaller range compared to the 8th graders.
c.) 30 and 18 are the medians. Subtract them and you get 12.
Hope I could help partially
Step-by-step explanation:
Regression analysis is used to infer about the relationship between two or more variables.
The line of best fit is a straight line representing the regression equation on a scatter plot. The may pass through either some point or all points or none of the points.
<u>Method 1:</u>
Using regression analysis the line of best fit is: 
Here <em>α </em>= intercept, <em>β</em> = slope and <em>e</em> = error.
The formula to compute the intercept is:

Here<em> </em>
and
are mean of the <em>y</em> and <em>x</em> values respectively.

The formula to compute the slope is:

And the formula to compute the error is:

<u>Method 2:</u>
The regression line can be determined using the descriptive statistics mean, standard deviation and correlation.
The equation of the line of best fit is:

Here <em>r</em> = correlation coefficient = 
and
are standard deviation of <em>x</em> and <em>y</em> respectively.
