How do you graph #2x + y = –1# by plotting points?

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Answer 1 · 2017-08-31T11:25:44

See a solution process below:

First, solve for two points which solve the equation and plot these points:

First Point:

For #x = 0#

#(2 * 0) + y = -1#

#0 + y = -1#

#y = -1# or #(0, -1)#

Second Point:

For #y = 0#

#2x + 0 = -1#

#2x = -1#

#(2x)/color(red)(2) = -1/color(red)(2)#

#x = -1/2# or #(-1/2, 0)#

We can next graph the two points on the coordinate plane:

graph{(x^2+(y+1)^2-0.025)((x+1/2)^2+y^2-0.025)=0 [-10, 10, -5, 5]}

Now, we can draw a straight line through the two points to graph the line:

graph{(2x+y+1)(x^2+(y+1)^2-0.025)((x+1/2)^2+y^2-0.025)=0 [-10, 10, -5, 5]}