Question 317642
Linear functions have the form, {{{y=mx+b}}}
Calculate the slope, {{{m}}},using the two points, ({{{9}}},{{{-39}}}) and ({{{16}}},{{{-81}}})
{{{m=(y2-y1)/(x2-x1)=(-81-(-39))/(16-9)=-42/7=-6}}}
Then use either point to find {{{b}}}.
{{{y=-6x+b}}}
{{{-39=-6(9)+b}}}
{{{-39=-54+b}}}
{{{b=15}}}
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{{{highlight(y=-6x+15)}}}