explain how to graph x + 3y = 9 using the x- and y-intercepts method.

Question

jim_thompson5910 · Answer

do you know how to find the x intercept?

anonymous · Answer

by looking on the right of the graph?

jim_thompson5910 · Answer

yes, but let's say you didn't know what the graph looked like or didn't have a graphing calculator

jim_thompson5910 · Answer

and you only had graphing paper

anonymous · Answer

ok,umm .. :( i dont know, i am not sure.

jim_thompson5910 · Answer

Let's find the x-intercept

jim_thompson5910 · Answer

Plug in y = 0 and solve for x


x + 3y = 9


x + 3(0) = 9


x + 0 = 9


x = 9


So the x-intercept is the point (9,0)

jim_thompson5910 · Answer

Let me know when you're ready to move on to the next part

anonymous · Answer

ok i am starting to understand that part ..:D

jim_thompson5910 · Answer

ready for the y-intercept?

anonymous · Answer

yes :D

jim_thompson5910 · Answer

Plug in x = 0 and solve for y


x + 3y = 9


0 + 3y = 9


3y = 9


y = 9/3


y = 3


So the y-intercept is the point (0,3)

jim_thompson5910 · Answer

Notice how everything flipped

jim_thompson5910 · Answer

So we have the x-intercept (9,0) and the y-intercept (0,3)

anonymous · Answer

yea i  noticed  :D

jim_thompson5910 · Answer

alright great

jim_thompson5910 · Answer

with these two points, you plot them on a grid or graph paper

jim_thompson5910 · Answer

then you draw a straight line through them to graph x+3y = 9

anonymous · Answer

omg i think i am starting to understand now :D

jim_thompson5910 · Answer

yay, that's good lol

anonymous · Answer

lol! thank you!

jim_thompson5910 · Answer

you're welcome