Question

Complete the equation of the line through 2,1 and 5,-8

Answer 1

Answer:

Step-by-step explanation:

Hello : let  A(2,1)    B(5,-8)

the slope is :   (YB - YA)/(XB -XA)

(-8-1)/(5-2)  = -9/3=-3

an equation is : y=ax+b     a is a slope

y = -3x +b

 

the line through point  (2,1) :  1= -(3)(2)+b    

b = 7

the equation is : y =-3x+7  

Answer 2

Answer:

y - 1 = -3(x - 2)

Step-by-step explanation:

As we move from the point (2, 1) to the point (5, -8), x (the run) increases by 3 and y (the rise) decreases by 9.  Thus, the slope of this line is

m = rise / run = -9/3, or m = -3.

Then the equation of the line (in point-slope form) is

y - 1 = -3(x - 2)