How do you graph #9x+2y=5#?

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Answer 1 · 2017-10-27T16:12:03

See a solution process below:

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

First Point: For #x = 1#

#(9 * 1) + 2y = 5#

#9 + 2y = 5#

#-color(red)(9) + 9 + 2y = -color(red)(9) + 5#

#0 + 2y = -4#

#2y = -4#

#(2y)/color(red)(2) = -4/color(red)(2)#

#y = -2# or #(1, -2)#

Second Point: For #x = -1#

#(9 * -1) + 2y = 5#

#-9 + 2y = 5#

#color(red)(9) - 9 + 2y = color(red)(9) + 5#

#0 + 2y = 14#

#2y = 14#

#(2y)/color(red)(2) = 14/color(red)(2)#

#y = 7# or #(-1, 7)#

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

graph{((x-1)^2+(y+2)^2-0.125)((x+1)^2+(y-7)^2-0.125)=0 [-20, 20, -10, 10]}

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

graph{(9x+2y-5)((x-1)^2+(y+2)^2-0.125)((x+1)^2+(y-7)^2-0.125)=0 [-20, 20, -10, 10]}