y =
x +

the equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y-intercept )
y =
x - 6 is in this form with slope m =

Parallel lines have equal slopes, thus
y =
x + c is the partial equation of parallel line
to find c , substitute (- 1, 5 ) into the partial equation
5 = -
+ c ⇒ c = 5 +
=

y =
x +
← equation of parallel line