Question 771914
first find equation of a line that passes through (-2,7) and (5,-3)

*[invoke change_this_name10094 -2, 7, 5, -3]

{{{y=-1.43x + 4.14}}}

if the point (3,a), means {{{x=3}}} and {{{y=a}}}, plug it in equation above

{{{a=-1.43*3 + 4.14}}}

{{{a=-4.29 + 4.14}}}

{{{a=-0.15}}}


{{{ drawing( 600, 600, -10, 10, -10, 10,circle(3,-0.15,0.1), locate(3,-0.5,p(3,-0.15)),graph( 600, 600, -10, 10, -10, 10, -1.43x + 4.14)) }}}