The value of 7 in this question is x
Number 19 I think is if you add the awnser to one of the numbers you where subtracting and you get the other number you where subtracting you are right like...
Lets say you had the problem 3-2 which is obviously 1 but if you did 2+1 it's 3 so that's how you check.
Answer: The scatterplot shows a positive correlation because the values of y increase as the values of x increase.
Which of the following is the best approximation of the correlation coefficient for the data displayed in the scatterplot? 0.5
Minus z both sides
0=x^2+wx+z
we can use quadratic formula or manually complete the square
let's use quadratic
for
0=ax^2+bx+c
![x= \frac{-b+/- \sqrt{b^2-4ac} }{2a}](https://tex.z-dn.net/?f=x%3D%20%5Cfrac%7B-b%2B%2F-%20%5Csqrt%7Bb%5E2-4ac%7D%20%7D%7B2a%7D%20)
given
0=1x^2+wx-z
a=1
b=w
c=-z
![x= \frac{-w+/- \sqrt{w^2-4(1)(-z)} }{2(1)}](https://tex.z-dn.net/?f=x%3D%20%5Cfrac%7B-w%2B%2F-%20%5Csqrt%7Bw%5E2-4%281%29%28-z%29%7D%20%7D%7B2%281%29%7D%20)
![x= \frac{-w+/- \sqrt{w^2+4z} }{2}](https://tex.z-dn.net/?f=x%3D%20%5Cfrac%7B-w%2B%2F-%20%5Csqrt%7Bw%5E2%2B4z%7D%20%7D%7B2%7D%20)
![x= \frac{-w+ \sqrt{w^2+4z} }{2}](https://tex.z-dn.net/?f=x%3D%20%5Cfrac%7B-w%2B%20%5Csqrt%7Bw%5E2%2B4z%7D%20%7D%7B2%7D%20)
or