Answer:
y = (2/15) x -(117/15)
Explanation:
To write the equation we should know the slope m and the y-intercept b .
m= (y2-y1)/(x2-x1)
For points (x1 = -9, y1 = -9) and (x2 = 6, y2 = -7)
m = (-7 - - 9)/(6 - - 9) = (-7 + 9)/(6 +9) = 2 / 15
The general equation of a line is
y= mx + b
Our equation is
y = (2/15) x +b
To find b, substitute one of the two points, we know are on the line, in our equation. For example, we can substitute point (-9,-9)
-9 = (2/15) (-9) +b , multiply -9 by 2/15
-9 = - (18/15) +b, add -18/15 on both sides
-9 + (18/15) = b, find common denominator and add
[(-9 ·15) +18]/15 = b , simplify
-117/15 = b
So our equation is:
y = (2/15) x -(117/15)