Question 952433

first recall that {{{y=mx +b}}} is the slope-intercept form of the linear equation where {{{m}}} is a slope and {{{b}}} is y-intercept 

the graph of {{{y=mx+b + 4}}} differ from that of {{{y=mx +b}}} in y-intercept (the point where the line crosses the y-axis) 

this one {{{y=mx+b + 4}}} has y-intercept {{{b+4}}}, and this one {{{y=mx +b}}}has y-intercept {{{b}}}; means that the graph of {{{y=mx+b + 4}}} intercept y-axis {{{4}}} units in higher point then the graph of {{{y=mx +b}}}

but, these two graphs have same slope which is {{{m}}} and that is telling us that lines are {{{parallel}}}

here is one example:

let first equation {{{y=mx+b + 4}} be {{{y = 4x +6+4}}}=> the slope is {{{m=4 }}} and the y-intercept is  point (0, 10), 
let second equation {{{y=mx+b }} be {{{y = 4x +6}}}=> the slope is {{{m=4 }}} and the y-intercept is  point (0, 6),

now, graph them  to see that these lines are parallel, just their the y-intercept point is different 

{{{ graph( 600, 600, -15, 15, -15, 15, 4x +6, 4x +10) }}}