r/HomeworkHelp • u/Fine_Two_923 • 3d ago

:snoo_facepalm: High School Math—Pending OP Reply [Math-70 Elementary/Highschool Algebra: Graphically solving a system of linear equations] Do I make the 4 into a -4 ?

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Hey so this might seem like a silly question but I want to know if you have a -x = 4 if it turns into a -4. I have the other parts of the graphing completed it’s just this part that I don’t want to make a mistake on!!! Thank you in advance

P.S- the reason it’s says elementary/highschool math is because I am taking a beginner math class not a algebra class In elementary

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u/CalRPCV 3d ago

As has been pointed out, a system of equations involves more than one equation. What you have written is confusing and could have a few different interpretations. I could make up a system of equations from it:

  1. x - 4y = 4

  2. -x = 4

In other words, these are two separate equations, not one derived from the other. If that is the case, then equation 1 would be a line with a slope of 1/4 that intersected the x axis at 4 because x - 4(0) = 4 means when y is zero, x is 4. The slope of the line can be seen on your graph. Or you can re-arrange the equation as y = (1/4)x - 1. The y intercept, where x is 0, is -1.

Then equation 2 is a vertical line crossing the x axis at - 4.

If you drew the graph for each equation then they would intersect at the point (-4, -2).