Question

What is an equation of the line that passes through the points (−5,−7) and (5,1)?

Answer 1

y = 0.8x - 3

Explanation:

Slope = (-7-1)/(-5-5) = -8/-10 = 0.8

When x = 5, y = 1

1 = 0.8(5) + c

1 = 4 + c

c = -3

y = 0.8x - 3

Answer 2

y = 4/5x -3

Explanation:

in order to do this :

firstly , find the midpoint of the points.

use the formula :

`(x1 + x2)/(2) , (y1 + y2)/(2)`

=
`(-5 + 5)/(2) , (-7 + 1)/(2)`

midpoint =(0 , -3)

secondly , get the gradient

use the formula :

`(y2-y1)/(x2-x1)`

=
`(1-(-7))/(5-(-5))`

=
`(8)/(10)`

simplified to 4/5

gradient = 4/5

Thirdly , create the equation

formula for the equation of a line

(Y-y1) = m( X-x1)

now use the values of the midpoint and the gradient(m)

y +7 = 4/5 (x + 5)

y = 4/5x + 4-7

y = 4/5x -3