Can this system of inequalities be solved for x?

AI Thread Summary
The discussion focuses on solving a system of inequalities represented by the equations x - 2y ≤ 54 and x + y ≥ 93. Participants emphasize that these inequalities define regions in the xy-plane rather than single points, making graphical representation essential for understanding their solutions. Algebraically, while one can manipulate the equations, the key is to graph the lines corresponding to the equalities to visualize the overlapping regions. The solution is not a single x-value but rather a set of (x,y) points within the intersection of the defined half-planes. Ultimately, the graphical method aids in identifying the solution set for the inequalities.
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Summary: Can these two equations be solved for x like a system of linear inequalities, and how?
##x- 2y \le 54##
##x + y \ge 93##

We start with
##x- 2y \le 54##
##x + y \ge 93##

Multiplying the second equation by 2, we have ##2x + 2y \ge 184##. We cannot seem to cancel the y out with the first equation because that would create an unclear inequality. So how do we solve it algebraically?

MENTOR NOTE: Moved to Precalculus Homework Help hence no template.
 
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Draw the individual inequalities as straight lines in the xy-plane.
How can you use this to figure out when both your inequalities are satisfied?
Is there a single x-value, or does it depend on y?
 
malawi_glenn said:
Draw the individual inequalities as straight lines in the xy-plane.
How can you use this to figure out when both your inequalities are satisfied?
Is there a single x-value, or does it depend on y?
That is solving it graphically. I would like to solve it algebraically.
 
Start with the equalities first to find a common x,y that solves them.

BEFORE WE GO ANY FURTHER: PLEASE SHOW SOME WORK.
 
The graphical solution will just be an aid for your algebra
 
annamal said:
Summary: Can these two equations be solved for x like a system of linear inequalities, and how?
##x- 2y \le 54##
##x + y \ge 93##
You don't want to "solve" for x and y. Because these inequalities define two entire regions (half planes), not two thin lines with one intersection point.
y=13 and x=80 is the solution of x-2y=54; x+y=23. That doesn't tell you much.
Instead, you want to graph the lines x-2y=54; x+y=23 to see what the two regions (half planes) of the two inequalities are. Then you can see where the regions overlap. All the (x,y) points in the overlap are the answer.
 
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