Like when its not in standard form, for example
3x + 2y = 18
how do I graph that?!
help please?
2007-01-10 13:16:06 · 5 answers · asked by xoh_myblueheaven 3 in Science & Mathematics ➔ Mathematics
okay i understand slope intercept form but the problem is written as part of a system and i've already solved the system, its {2,6} meaning the point of intersection must be at those coordinates right?
but i cant figure out how to graph that one line, because when i put it in slope intercept form its not intersecting at the right point
do i have to put it in point slope form? how do i rework the problem so that it gives 1 point, like in point slope form?
2007-01-10 13:52:12 · update #1
okay i understand slope intercept form but the problem is written as part of a system and i've already solved the system, its {2,6} meaning the point of intersection must be at those coordinates right?
but i cant figure out how to graph that one line, because when i put it in slope intercept form its not intersecting at the right point
do i have to put it in point slope form? how do i rework the problem so that it gives 1 point, like in point slope form? instead of using the y intercept
2007-01-10 13:52:35 · update #2
then you have to put the equation in standform
3x+2y=18
2y= -3x+18
y= -3/2x+9
2007-01-10 13:20:32 · answer #1 · answered by 7 · 0⤊ 0⤋
you have to rearrange the equation to make y the subject of the formula:
3x+2y=18
2y= -3x+18
y= -3/2x+9
your equation is now of the farmiliar form y=mx+c. the y intercept is 9, that is to say the line cuts the y-axis at y=9 and the slope is
-3/2.
the line cuts the x-axis when y=0, putting that into the equation gives
0=-3/2x+9
therefore x=18/3.
You now know that the graph passes through the two points y=9 and x=18/3, so the graph you want is given by the line that connects these points
2007-01-10 21:42:24 · answer #2 · answered by Elsen 2 · 0⤊ 0⤋
Put the equation in y-intercept form y=mx+b
b is the y-intercept, and m is the slope of the line.
3x+2y=18
2y=-3x+18
y=-(3/2)x+18
the y-intercept is 18, so make a point at (0,18). Then graph the rest of the line using the slope, which is negative 3/2.
2007-01-10 21:26:18 · answer #3 · answered by Someone 3 · 0⤊ 0⤋
As was mentioned... get into standard form... also, if you're like me, must put in some values for X and Y that work and graph those.
2007-01-10 21:24:04 · answer #4 · answered by geek49203 6 · 0⤊ 0⤋
well, u can start by putting it in standard form which is
y=-3/2x+18
then make a table chart and pick points and graph all the points. its that easy!
2007-01-10 21:36:28 · answer #5 · answered by ashesanne 2 · 0⤊ 0⤋