Question

A line passes through the points (1, 4) and (3, 4). Which is the equation of the line?

O y=-4x+8
O y=-2x + 6
O y=-*x+2
O y=2x + 2

Answer 1

y = 4

Explanation:

Calculate the slope m using the slope formula

m =
`(y_(2)-y_(1) )/(x_(2)-x_(1) )`

with (x₁, y₁ ) = (1,4) and (x₂, y₂ ) = (3, 4)

m =
`(4-4)/(3-1)` =
`(0)/(2)` = 0

This indicates the line is horizontal and parallel to the x- axis with equation

y = c

where c is the value of the y- coordinates the line passes through.

The line passes through (1, 4) and (3, 4) with y- coordinates of 4, thus

y = 4 ← equation of line

Answer 2

None of the answers is correct based on the points given

Explanation:

1. Use the slope formula (see image)

`(4-4)/(3-1) = 0`

Based on the points given the slope is actually undefined.