Answer:
[tex]\large\boxed{y=-\dfrac{3}{2}x+11}[/tex]
Step-by-step explanation:
The slope-intercept form of an equation of a line:
[tex]y=mx+b[/tex]
m - slope
b - y-intercept
The formula of a slope:
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
We have the point A(8, -1) and B(-4, 17). Substitute:
[tex]m=\dfrac{17-(-1)}{-4-8}=\dfrac{18}{-12}=-\dfrac{3}{2}[/tex]
The equation of a line:
[tex]y=-\dfrac{3}{2}x+b[/tex]
Put the coordinates of the point A(8, -1) to the equation of a line:
[tex]-1=-\dfrac{3}{2}(8)+b[/tex]
[tex]-1=-3(4)+b[/tex]
[tex]-1=-12+b[/tex] add 12 to both sides
[tex]11=b\to b=11[/tex]
Finally we have the equation of a line in a slope-intercept form:
[tex]y=-\dfrac{3}{2}x+11[/tex]