Answer:
1) The linear regression model is y = -0.0348·x + 13.989
2) The correlation coefficient is -0.0725
3) The strength of the model is strong - association
Step-by-step explanation:
1)
X Y XY X²
27 13 351 729
65 12 780 4225
83 11 913 6889
109 10 1090 11881
142 9 1278 20164
175 8 1400 30625
∑ 601 63 5812 74513
From y = ax + b, we have
b = 1/n(∑y -a∑x) = 1/6(63 - (0.0348)×601) = 13.989
Therefore, the linear regression model is y = -0.0348·x + 13.989
2)
![r = \frac{n\sum xy - \sum x\sum y }{\sqrt{[n\sum x^{2}-\left (\sum x \right )^{2}] [n\sum y^{2}-\left (\sum y \right )^{2}]}} = \frac{6 \times 5812 - 601 \times 63}{\sqrt{[6 \times 74513-601^{2}] [6 \times 3969 - 63^2]} } = - 0.0725](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7Bn%5Csum%20xy%20-%20%5Csum%20x%5Csum%20y%20%7D%7B%5Csqrt%7B%5Bn%5Csum%20x%5E%7B2%7D-%5Cleft%20%28%5Csum%20x%20%20%5Cright%20%29%5E%7B2%7D%5D%20%5Bn%5Csum%20y%5E%7B2%7D-%5Cleft%20%28%5Csum%20y%20%20%5Cright%20%29%5E%7B2%7D%5D%7D%7D%20%20%3D%20%5Cfrac%7B6%20%5Ctimes%205812%20%20-%20601%20%5Ctimes%2063%7D%7B%5Csqrt%7B%5B6%20%5Ctimes%2074513-601%5E%7B2%7D%5D%20%5B6%20%20%5Ctimes%203969%20-%2063%5E2%5D%7D%20%7D%20%3D%20-%200.0725)
3) The strength is - association.
Answer:
Step-by-step explanation:
The system of equations given are:
5x - y + z = -6 ------------- i
2x + 7y + 3z = 8 ---------- ii
x + 2z = 6 ----------------- iii
Let us deal with equation i and ii first since they have 3 variables x, y and z;
5x - y + z = -6 x 7
2x + 7y + 3z = 8 x 1
35x - 7y + 7z = -42 ---- iv
2x + 7y + 3z = 8 ---- v
Add equation iv and v;
37x + 10z = -34 ------vi
So, let us solve equation vi and iii:
x + 2z = 6 - ---------- iii x 10
37x + 10z = -34 --- iv x 2
10x + 20z = 60 vi
74x + 20z = -68 vii
Subtract vi - vii;
-64x = 128
x = -2
So; put x = -2 into iii;
x + 2z = 6
-2 + 2z = 6
2z = 6 + 2 = 8
z = 4
Put x = -2 and z = 4 into equation i;
5(-2) - y + 4 = - 6
-10 -y +4 = -6
-6 - y = -6
-y = 0
y = 0
Answer:
Sasha stopped working at 12:10 PM
Step-by-step Explanation
8:30 + 3 hours and 40 minutes = 12:10 PM
Mark as brainliest if it's right!
Answer:
The 2 integers would be: 2 and 8
Step-by-step explanation:
2 + 8 = 10
Reciprocal of 2: 1/2
Reciprocal of 8: 1/8
1 / 2 - 1 / 8 = 4/8 - 1/8 = <u>3/8</u>
Answer:
8x^2 + 15x -9
Explanation:
Distribute and combine
