Question 1198167
 {{{ax +by=c}}}

{{{m=2}}}, ({{{8}}},{{{8}}})

use point slope formula

{{{y-y[1]=m(x-x[1])}}}

{{{y-8=2(x-8)}}}

{{{y-8=2x-16}}}

{{{y-2x=-16+8}}}.....rearrange left side

{{{-2x+y=-8}}} -> your answer


{{{ drawing( 600, 600, -10, 10, -10, 10,
circle(8,8,.12),locate(8,8,p(8,8)),
graph( 600, 600, -10, 10, -10, 10, 2x-8)) }}}