http://prntscr.com/99ejg2
@Directrix
I would suggest you represent the bounding line that divides the solution plane with the non-solution one. For that, we will find all the points that satify: \(y=-\frac{ 3 }{ 4 }x+3\) And this is the equation of the line written in it's explicit form, if you have trouble representing a line by it's equation, you can spot two points by giving any value to "x" and solving for "y". Just to repeat myself a little, we must first find the boundry line of the divided planes, for that we turn the inequality sign into an "=" sign.
Good, now, in order to see what region will determine the solution, we pick any point not belonging to the line and plot it in, operate the corresponding operations and if the inequality is satisfied then the point must belong to the solution region. For this, people use most commonly the origin, so by that I mean you plot the point (0,0) in the inequality: \(y \le -\frac{ 3 }{ 4 }x+3\)
Yes, you represented the point, but I want you to insert it into the inequality, what you do is replace the x,y values of the point to the inequality: \[y \le -\frac{ 3 }{ 4 }x+3\] \[0 \le -\frac{ 3 }{ 4 }(0)+3\]
That is correct.
No, you have to simplify the expression: \[0 \le -\frac{ 3 }{ 4 }(0)+3\] it ends with: \[0 \le 3\] And zero is less than three so that means that the origin actually is a point belonging to the solution plane.
@Directrix
Okay, I see your graph. It is correct.
(1,2) is in the solution set and means 1 pound of apples and 2 pounds of oranges which the girl can buy for a total cost which is less than $12.
Repair part B. (4,3) is not part of the solution set. @Diana.xL
thnx
You are welcome.
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