Question

use linear regression to find a function that fits the following points. (-2, -1) (3, 9) ?x +

Explanation:

Step1: Calculate the slope \(m\)

The formula for slope \(m=\frac{y_2 - y_1}{x_2 - x_1}\).
Let \((x_1,y_1)=(-2,-1)\) and \((x_2,y_2)=(3,9)\).
\(m=\frac{9-(-1)}{3-(-2)}=\frac{9 + 1}{3+2}=\frac{10}{5}=2\)

Step2: Find the \(y\) - intercept \(b\)

Use the point - slope form \(y=mx + b\). Substitute \(m = 2\) and the point \((x,y)=(3,9)\) (we could also use \((-2,-1)\)).
\(9=2\times3 + b\)
\(9 = 6 + b\)
Subtract 6 from both sides: \(b=9 - 6=3\)

Answer:

\(2x+3\)