Question

The points (-1,2) and (4,y) have a slope of -4/5. what is the y-coordinate of the point (4,y)

Answer 1

y = - 2

Explanation:

Calculate the slope m using the slope formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (- 1,2) and (x₂, y₂ ) = (4, y)

m =
`(y-2)/(4+1)`, hence

`(y-2)/(5)` = -
`(4)/(5)` ( cross- multiply )

5(y - 2) = - 20 ( divide both sides by 5 )

y - 2 = - 4 ( add 2 to both sides )

y = - 2

coordinates of point are (4, - 2)