Any straight line on the coordinate plane can be described by the equation
y=mx+b
Where:
x,y are the coordinates of any point on the line
m is the slope of the line
b is the intercept (where the line crosses the y-axis) .
The slope m can be found beetween two points:
[tex]m=\frac{y_2-y_1}{x_2-x_1} = \frac{-3-3}{1-(-5)} = -1[/tex]
m and one of the known points is inserted in the equation y=mx+b
[tex]3=-1*-5+b[/tex] ⇒ [tex]1\cdot \:5+b=3[/tex] ⇒ [tex]5+b-5=3-5[/tex] ⇒[tex]b=-2[/tex]
Then the equation is:
y = mx + b ⇒[tex]y=-x-2[/tex]
