Question 664321

1. {{{y=2x}}}

set {{{y=0}}} and find the {{{x-intercept}}} 

{{{0=2x}}}

{{{0=x}}}....the {{{x-intercept}}} is at ({{{0}}},{{{0}}})

and set {{{x=0}}} to find {{{y-intercept}}}

{{{y=2*0}}}

{{{y=0}}}....the {{{y-intercept}}} is at ({{{0}}},{{{0}}})

to graph this line we need one more point since the {{{x-intercept}}} and the {{{y-intercept}}} lie in same point


let {{{x=1}}}

{{{y=2*1}}}

{{{y=2}}}.....the point is at ({{{1}}},{{{2}}})


{{{ graph( 600, 600, -10,10, -10, 10, 2x) }}}



2. {{{y=-2x}}}

set {{{y=0}}} and find the {{{x-intercept}}} 

{{{0=-2x}}}

{{{0=x}}}....the {{{x-intercept}}} is at ({{{0}}},{{{0}}})

and set {{{x=0}}} to find {{{y-intercept}}}

{{{y=-2*0}}}

{{{y=0}}}....the {{{y-intercept}}} is at ({{{0}}},{{{0}}})

to graph this line we need one more point since the {{{x-intercept}}} and the {{{y-intercept}}} lie in same point


let {{{x=1}}}

{{{y=-2*1}}}

{{{y=-2}}}.....the point is at ({{{1}}},{{{-2}}})


{{{ graph( 600, 600, -10,10, -10, 10, -2x) }}}



3. {{{y=(1/3)x+1}}}

set {{{y=0}}} and find the {{{x-intercept}}} 

{{{0=(1/3)x+1}}}

{{{-1=(1/3)x}}}

{{{-3=x}}}....the {{{x-intercept}}} is at ({{{-3}}},{{{0}}})

and set {{{x=0}}} to find {{{y-intercept}}}

{{{y=(1/3)*0+1}}}

{{{y=1}}}....the {{{y-intercept}}} is at ({{{0}}},{{{1}}})


{{{ graph( 600, 600, -10,10, -10, 10, (1/3)x+1) }}}