Question

Complete the equation of the line through (2, 1) and (5, -8). Use exact numbers. y =​

Answer 1

Answer:

y = - 3x + 7

Step-by-step explanation:

The equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

Calculate m using the slope formula

m = $\frac{y_{2}-y_{1} }{x_{2}-x_{1} }$

with (x₁, y₁ ) = (2, 1) and (x₂, y₂ ) = (5, - 8)

m = $\frac{-8-1}{5-2}$ = $\frac{-9}{3}$ = - 3 , then

y = - 3x + c ← is the partial equation

To find c substitute either of the 2 points into the partial equation

Using (2, 1 ), then

1 = - 6 + c ⇒ c = 1 + 6 = 7

y = - 3x + 7 ← equation of line

Answer 2

Answer:

Step-by-step explanation:

given: (2,1) & (5-8)

first find the slope,

m= (Y2-Y1) / (X2-X1)    

m=(-8-1)/(5-2)

m=(-9)/(3)

m=-3

we have y=-3x+b

use any point to sub in x and y

1=-3(2)+b

1+6=b

b=7               therefore, y=-3x+7 is the equation