The <u>correct answer</u> is:
0.872.
Explanation:
The correlation coefficient of a regression line is a measure of how closely the line fits our data. Negative correlation coefficients represent decreasing lines; positive correlation coefficients represent increasing lines.
The closer a correlation coefficient is to +1 or -1, the better the fit; a perfect positive fit is r=1 and a perfect negative fit is r=-1.
We can see in the graph that the line is very close to our data, so it is a pretty good fit.
The line is increasing; this means we want a correlation coefficient that is close to 1.
The best choice is 0.872.
the answer to your question is -5×
The area of the shaded region will be the area of the rectangle minus the area of the white square inside of it:
((x+10)(2x+5)) - ((x+1)(x+1))
First, FOIL both of the areas separately:
(2x^2 + 5x + 20x + 50) - (x^2 + x + x + 1)
Simplify within the parentheses by adding like terms:
(2x^2 + 25x + 50) - (x^2 + 2x + 1)
Now, subtract one equation from the other:
2x^2 + 25x + 50
-x^2 - 2x - 1
= x^2 + 23x + 49
This will be the equation for the area.
1. addition
2. subtraction