Inactive Tutor answered 02/07/18
Tutor
New to Wyzant
parallel lines have similar slope, and we need at least two points to find a slope (in fact for each line we need at least two points)
(slope)m=(y2-y1)/(x2-x1)=(7-3)/(2-(-2))=1
In general, the equation of a line is Y=mx+b which b is called intercept and can be calculated by plugging the given point in the general equation. remember m=1
Y=X+b ==> 9=1+b ==>b=8
Y=X+8 is the equation of the line that passes through (1,9) and is parallel to the line passing through (2, 7) and (−2, 3)