Question 815135
bill speed = 6km/h
bill distance = y
bill time = x

distance = rt
y=6x

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Sue

distance =y
speed = 12 km/h
time = (x-1/2)

y= 6(x-1/2)

y=12x-6


generate points for both equations
and draw the lines
x value of the intersection point is the time she overtakes
{{{drawing(500,500,-10,10,-10,10,grid(1),graph(500,500,-10,10,-10,10,y=6x,y=12x-6))}}}


x value is 1 hour