Graphing equations?

Question

Hi i want to know if anyone can help me on these equations. They need to be order pair.
Thanks

1) 2x + y = 9

2) -x - y = - 8

3) - 3x + 4y = 2

4) - 2x - y = - 3

Answer 1

The simplest method for graphing these equations is the segment form given by

(1) x/m + y/n = 1

where (m, 0) and (0, n) are the points where the line given by (1) intersects x and y axes respectively.
So you draw a line through those two points and you got yourself a graph

Let's splve number 1

2x + y = 9
devide it by 9 you get that
2x/9 + y/9 = 1
so m = 9/2, n = 9
Draw the line through points (9/2, 0) and (0, 9), and there you have it.

you can solve the other three yourself now...

Answer 2

In order to get your ordered pair, you should probably put the equations into slope-intercept form and go from there. To do this. . .

First, subtract 2x from both sides to get y by itself.

y = -2x + 9

Now you've got something that's easier to work with. You know that 9 is your y-intercept and that -2/1 is your slope (remember that slope is rise over run).

To find your ordered pair, it would help to have the y-intercept graphed. When you plot the 9 on the y-axis, use the slope to help find the point on the line. Go down two (-2 part of the slope; the rise) and to the right 1 (1 part of the slope; the run). The point you should end up at is (1,7). In the slope, it doesn't matter if the negative sign is on the top or on the bottom, just as long as it's there. You could also go up 2 and to the left 1 and you would get (-1, 11).

Your two points are (1,7) and (-1, 11). To make sure they're right, plug them back into the original equation to see if you get the right answer.

2(1) + 7 = 2 + 7 = 9
2(-1) + 11 = -2 + 11 = 9

Both points check, so you can use either one.

I'll do another one, without all the explanation this time.

3) Get it into slope-intercept form.

4y = 3x + 2
y = 3/4x + 1/2

Now you have your slope (3/4) and your y-intercept (1/2). To find your point, go up 3 and to the right 4 and get (4, 3.5) or go down 3 and to the left 4 and get (-4, -2.5).

Plug both points back in to make sure they check.

-3(4) + 4(3.5) = -12 + 14 = 2
-3(-4) + 4(-2.5) = 12 + -10 = 2

Since both points check, you can use either (-4, -2.5) or (4, 3.5).

Now you should be able to do the rest the same way I did the two above. Good luck!

Answer 3

These equations represent lines. To graph a line, two points written as ordered pairs, (x,y), are needed.
1) 2x + y = 9

Let x = 0 :
2(0) + y = 9
y = 9
So, (0,9) is one point.

For a second point, substitute, y = 1:
2x + 1 = 9
2x = 9 -1 = 8
x = 8/2 = 4.
The point, (4,1) is on the line.

Plot the points & draw the line.

Answer 4

x intercept is a coordinates of the points that a graph has in common with the x-axis. to solve for the x intercept

y = 0

2x + y = 9

2x + 0 = 9

2x = 9

2xx/2 = 9/2

x = 4.5

The ordered pain is (4.5, 0)

The solution set is { 4.5, 0 }

- - - - - - -

y intercept a coordinates of the points on a graph that hs in common with the y -axis.

solving for the y-intercept

x = 0

2x + y = 9

2(0) + y = 9

0 + y = 9

y = 9

The ordered pair is (0, 9)

The solution set is { 0, 9 }

- - - - - - s-

Answer 5

just fill in two point (x,y) that satisfy the equaqtion and draw a line thruogh these 2 points.

for instance 1)
take x = 4, then y = 1; tahke x = 1 then y = 7
so a line throuph points (4,1) and (1,7) is the grapgh