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NO LINKS!! Please help me with this problem. Part 5gg​

NO LINKS!! Please help me with this problem. Part 5gg​-example-1
User Jumabek Alikhanov
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1 Answer

15 votes
15 votes

Answer:

(-4, -1]

Explanation:

Given inequality:


(x+10)/(x+4) \geq 3

When the denominator of a rational function is zero, the function is undefined. Therefore, x ≠ -4, so x = -4 is a boundary point for the solution to the inequality.

Solve the inequality as though it were an equation.


\implies(x+10)/(x+4) =3


\implies x+10 =3(x+4)


\implies x+10 =3x+12


\implies -2x=2


\implies x=-1

The real solution to the equation is also a boundary point for the solution to the inequality.

Make the x = -1 boundary point a closed circle as the original inequality includes equality.

Make the x = -4 boundary point an open circle as it is not included.

Three regions have been created:

  • x < -4
  • -4 > x ≤ -1
  • x ≥ -1

Select points from the different regions and test to see if they satisfy the original inequality:


x=-5 \implies (-5+10)/(-5+4)=(5)/(-1)=-5 \\geq 3


x=-2 \implies (-2+10)/(-2+4)=(8)/(2)=4 \geq 3


x=0 \implies (0+10)/(0+4)=(10)/(4)=2.5 \\geq 3

Since x = -5 does not satisfy the original inequality, the region x < -4 is not part of the solution.

Since x = -2 satisfies the original inequality, the region -4 > x ≤ -1 is part of the solution.

Since x = 0 does not satisfy the original inequality, the region x ≥ -1 is not part of the solution.

Therefore, the solution in interval notation is:

  • (-4, -1]

To graph the solution set:

  • Place an open circle at x = -4.
  • Place a closed circle at x = -1.
  • Connect the circles with a line between them.
NO LINKS!! Please help me with this problem. Part 5gg​-example-1
User Meytal
by
2.6k points