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What is the equation of the graph below?

2x + y = 8

-4x + 8y = 1

-2x + y = 8

4x - 8y = 1

4x + 8y = 1

What is the equation of the graph below? 2x + y = 8 -4x + 8y = 1 -2x + y = 8 4x - 8y-example-1

2 Answers

3 votes

Answer:

-2x+y=8

Explanation:

First, change the equations into slope-intercept form. See the attached image for how to change the equations into slope-intercept form (if you have any questions on how to do this, let me know in the comments!)

Remember that b is the y-intercept. The y-intercept in the graph is 8, so the answer has to be an equation ending with 8 as the b.

This leaves us with 2x+y=8 and -2x+y=8 (their slope-intercept form is y=-2x+8 and y=2x+8, respectively) as our only options.

Then, we have to find the equation with a slope, which is m, that matches the slope of the graph.

We can figure out the graph's slope by using the
(y_2-y_1)/(x_2-x_1) formula.

We need two points on the graph to find the slope. We can use (0,8) and (-4,0) for this.

We need to input the coordinates into the formula. Make sure the order of each y and x match up with the coordinates (ex: you can do
(y_2-y_1)/(x_2-x_1) and
(y_1-y_2)/(x_1-x_2), but you cannot do
(y_1-y_2)/(x_2-x_1) or
(y_2-y_1)/(x_1-x_2)).

Let's do
(0-8)/(-4-0), which becomes
(-8)/(-4). This simplifies to
(2)/(1), which becomes 2. Thus, our answer needs to have a slope of 2.

Again, our options are 2x+y=8 and -2x+y=8 (their slope-intercept form is y=-2x+8 and y=2x+8, respectively). Looking at their slope-intercept form, the second equation, y=2x+8 is the one with the slope of 2 (the other has a slope of -2). Thus, -2x+y=8 is your answer!

Hope that helps! <3

Disclaimer: I am not responsible for anything you get incorrect, as I only have the context and information you provide, and I give my response based on my knowledge supported with credible information from experts and online professional articles.

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What is the equation of the graph below? 2x + y = 8 -4x + 8y = 1 -2x + y = 8 4x - 8y-example-1
User Gu XiaoWan
by
4.1k points
3 votes

Answer:

-2x+y=8

Explanation:

In slope-intercept form -2x+y=8 is y=2x+8.

After converting, it is easier to graph.

The constant 8 is the y intercept.

The slope is 2.

Knowing these values, one will find (0,8).

From that coordinate one will go up 2 right one then down 2 left 1 till the graph is complete.

User Lovlesh
by
4.5k points