What is the slope and intercept of #-x-10y=20#?

1 Answer
May 21, 2016

Answer:

Slope: #(-1/10)color(white)("XXXXX")#y-intercept: #(-2)#

Explanation:

Given
#color(white)("XXX")-x-10y=20#

Convert this into the slope-intercept form
#color(white)("XXX")y=color(green)(m)x+color(blue)(b)#
with slope #color(green)(m)# and y-intercept #color(blue)(b)#

#-x-10y=20#
#color(white)("XXX")rarr -10y=x+20#

#color(white)("XXX")rarr y= color(green)(-1/10)xcolor(blue)(-2)#

which is the slope-intercept form
with slope #color(green)(""(-1/10))# and y-intercept #color(blue)(""(-2))#

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Typically it is only the y-intercept that is required in this type of question, but if the x-intercept is also desired:

Set #y=0# in the original equation (the x-intercept occurs on the X-axis where #y=0#).

#color(white)("XXX")-x-10(0)=20#

#color(white)("XXX")rarr x=color(red)(""(-20))#

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Here is what the graph of this equation looks like:
graph{-x-10y=20 [-24.6, 3.86, -7.37, 6.87]}