Question 269702
x, how many problems
y, how much time
points (x,y)


Points described are (5,40) and (10,70).


Slope for the linear relationship
{{{(70-40)/(10-5)}}}
{{{30/5}}}
{{{6}}}


Taking point (5,40) and using found slope 6
{{{(y-40)/(x-5)=6}}}

{{{y-40=6(x-5)}}}

{{{y-40=6x-30}}}

{{{y=6x-30+40}}}

{{{y=6x+10}}}


Finding y if x=25
{{{y=6*25+10}}}
{{{highlight(y=160)}}}{{{minutes}}}