Write a system of linear inequalities so the points (1, 2) and (4, -3) are solutions of the system, but the point (-2, 8) is not a solution of the system.

Respuesta :

Answer: [tex]\left \{ {{y\leq -\frac{5}{3}x + \frac{11}{3}} \atop {y < 8}} \right[/tex]

Step-by-step explanation:

(1, 2) and (4, -3)

First, find the slope (m): [tex]\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]

m = [tex]\frac{-3-2}{4-1}[/tex]

   = [tex]-\frac{5}{3}[/tex]

Next, choose ONE of the points and input the point and slope into the Point-Slope formula: y - y₁ = m(x - x₁)

y - 2 = [tex]-\frac{5}{3}[/tex](x - 1)

y - 2 = [tex]-\frac{5}{3}x[/tex] + [tex]\frac{5}{3}[/tex]

y      = [tex]-\frac{5}{3}x[/tex] + [tex]\frac{11}{3}[/tex]

Then, determine which inequality symbol will result in (-2, 8) being False (since it is not a solution):

y ___ [tex]-\frac{5}{3}x[/tex] + [tex]\frac{11}{3}[/tex]

8 ___ [tex]-\frac{5}{3}(-2)[/tex] + [tex]\frac{11}{3}[/tex]

8 ___ [tex]\frac{1}{3}[/tex]

8 > [tex]\frac{1}{3}[/tex]

so ≤ makes the statement False

⇒ y ≤ [tex]-\frac{5}{3}x[/tex] + [tex]\frac{11}{3}[/tex]

****************************************************************

If you need a "system" of inequalities, then you need another equation.

There are infinite possibilities. Graph the points to see what works.  

y < 8   or  x > -2 are two examples.


---> I just realized that the system can be simpler than what I did above:

[tex]\left \{ {{x>-2} \atop {y < 8}} \right[/tex]



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