Question 1032369
<pre>
You plot them first: 

{{{drawing(400,400,-5,15,-5,15,graph(400,400,-5,15,-5,15),



circle(-2,9,0.15),circle(-2,9,0.13),circle(-2,9,0.11),circle(-2,9,0.09),circle(-2,9,0.07),circle(-2,9,0.05),circle(-2,9,0.03),circle(-2,9,0.01),





circle(1,6,0.15),circle(1,6,0.13),circle(1,6,0.11),circle(1,6,0.09),circle(1,6,0.07),circle(1,6,0.05),circle(1,6,0.03),circle(1,6,0.01),

circle(4,3,0.15),circle(4,3,0.13),circle(4,3,0.11),circle(4,3,0.09),circle(4,3,0.07),circle(4,3,0.05),circle(4,3,0.03),circle(4,3,0.01),

circle(7,0,0.15),circle(7,0,0.13),circle(7,0,0.11),circle(7,0,0.09),circle(7,0,0.07),circle(7,0,0.05),circle(7,0,0.03),circle(7,0,0.01) )}}}

Then you look and see what you'd have if you connected them.
Looks like you'd get a straight line.

So you connect them:

{{{drawing(400,400,-5,15,-5,15,graph(400,400,-5,15,-5,15),

line(-2,9,7,0),

circle(-2,9,0.15),circle(-2,9,0.13),circle(-2,9,0.11),circle(-2,9,0.09),circle(-2,9,0.07),circle(-2,9,0.05),circle(-2,9,0.03),circle(-2,9,0.01),

circle(1,6,0.15),circle(1,6,0.13),circle(1,6,0.11),circle(1,6,0.09),circle(1,6,0.07),circle(1,6,0.05),circle(1,6,0.03),circle(1,6,0.01),

circle(4,3,0.15),circle(4,3,0.13),circle(4,3,0.11),circle(4,3,0.09),circle(4,3,0.07),circle(4,3,0.05),circle(4,3,0.03),circle(4,3,0.01),

circle(7,0,0.15),circle(7,0,0.13),circle(7,0,0.11),circle(7,0,0.09),circle(7,0,0.07),circle(7,0,0.05),circle(7,0,0.03),circle(7,0,0.01) )}}}

And it looks like the y-intercept, (the point where the line intercepts
the y-axis) is the point (0,7), in green below:

{{{drawing(400,400,-5,15,-5,15,graph(400,400,-5,15,-5,15),

line(-2,9,7,0),

circle(-2,9,0.15),circle(-2,9,0.13),circle(-2,9,0.11),circle(-2,9,0.09),circle(-2,9,0.07),circle(-2,9,0.05),circle(-2,9,0.03),circle(-2,9,0.01),

circle(1,6,0.15),circle(1,6,0.13),circle(1,6,0.11),circle(1,6,0.09),circle(1,6,0.07),circle(1,6,0.05),circle(1,6,0.03),circle(1,6,0.01),

green(circle(0,7,0.15),circle(0,7,0.13),circle(0,7,0.11),circle(0,7,0.09),circle(0,7,0.07),circle(0,7,0.05),circle(0,7,0.03),circle(0,7,0.01)),

circle(4,3,0.15),circle(4,3,0.13),circle(4,3,0.11),circle(4,3,0.09),circle(4,3,0.07),circle(4,3,0.05),circle(4,3,0.03),circle(4,3,0.01),
green(locate(.2,7.4,"(0,7)")),
circle(7,0,0.15),circle(7,0,0.13),circle(7,0,0.11),circle(7,0,0.09),circle(7,0,0.07),circle(7,0,0.05),circle(7,0,0.03),circle(7,0,0.01) )}}}

Edwin</pre>