Question 70118
For what value of k does the line {{{kx+7y=10}}} have a slope of 3

The standard form (slope-intercept) for this equation is:

{{{y=mx+b}}}   where m is the slope and b is the y-intercept

Lets put the equation into standard form:

{{{kx+7y=10}}}  subtract kx from both sides

{{{kx-kx+7y=-kx+10}}}

{{{7y=-kx+10}}}  divide both sides by 7

{{{y=-(k/7)x+10}}} this is now in standard form
{{{m=-k/7}}} so
{{{-k/7=3}}} multiply both sides by -7
{{{k=-21}}}----------------------------------ans


Hope this helps----ptaylor