Question

What is the equation of a line that passes through points (-1, 2) and (5, 2)?


y - 2 = 0
x - 2 = 0
y - x - 2 = 0

Answer 1

first get what was given to you into an equation that you know...

Answer 2

so you would first have to find the slope of the line.
\[slope = \frac{ rise }{ run } = \frac{ y _{2}-y _{1} }{ x _{2}-x _{1} }\]when given the points (x1, y1) and (x2, y2)
so when given the points (-1, 2) and (5, 2)
you would plug in x1 = -1 , y1 = 2 , x2 = 5 , y2 = 2

but when you try to get the slope, you get a 0 in the numerator
therefore you're slope would be 0 (a horizontal line)
(note that if you get a 0 in the denominator, you would get a vertical line)

then slope-intercept form is: y = mx + b
when m = slope and b = y-intercept
but slope = 0
so y = 0 + b
y = b
so you would just plug in the y value of a given coordinate for b
(since it is a horizontal line)
(-1, 2)
^
so y = 2
then to match it up with your options get all values to one side so minus 2 from both sides...
y = 2
- 2 -2
y -