<PRE><B>Question 396206</B>
How do you find the value for k so that the line through (k,-10) and (5,-6) is parallel to y= -1/4x + 3
:
Parallel lines have the same slope, {{{-1/4}}} is the slope in this problem
Use the slope formula: m = {{{(y2-y1)/(x2-x1)}}}
Assign the give points as follows
x1=k; y1=-10
x2=5; y2=-6
:
{{{(-6-(-10))/(5-k)}}} = {{{-1/4}}}
{{{(-6+10)/(5-k)}}} = {{{-1/4}}}
{{{4/(5-k)}}} = {{{-1/4}}}
cross multiply
4*4 = -1(5-k)
16 = k - 5
16 + 5 = k
k = 21
:
:
Check this using substitution in the slope formula</PRE>