Question 911091
Both are linear so each side needs two points. {{{x=0}}} is one. Choose the others as you will, say{{{x=-5}}} and {{{x=5}}}
{{{x=-5}}}
{{{y=1+(-5)=-4}}}
(-5,-4)
.
.
.
{{{x=5}}}
{{{y=1-5=-4}}}
(5,-4)
.
.
.
And {{{x=0}}}
{{{y=1}}}
(0,1)
.
.
.
{{{drawing(300,300,-6,6,-6,6,grid(1),
circle(5,-4,0.3),circle(-5,-4,0.3),circle(0,1,0.3),
blue(line(-10,-9,0,1),blue(line(10,-9,0,1))))}}}