Question 720029
Any line perpendicular to the line
{{{ y = mx + b }}}
has a slope = {{{ -1/m }}}
In this case the slope is {{{ -1/4 }}}, so
{{{ m = (-1)/( -1/4) }}}
{{{ m = 4 }}}
Now I can use the point-slope formula
{{{ ( k -(-7) ) / ( 3 -(-7) ) = 4 }}}
{{{ ( k + 7 ) / ( 3 + 7 ) = 4 }}}
{{{ k + 7 = 4*10 }}}
{{{ k = 40 - 7 }}}
{{{ k = 33 }}}