Respuesta :

Answer:

Hence final answer is [tex]x \leq -3[/tex] or [tex]2 \leq x<7[/tex]

correct choice is A because both ends are open circles.

Step-by-step explanation:

Given inequality is [tex]\frac{x^2+x-6}{x-7}\leq 0[/tex]

Setting both numerator and denominator =0 gives:

[tex]x^2+x-6=0[/tex],  x-7=0

or  [tex](x+3)(x-2)=0[/tex],  x-7=0

or x+3=0, x-2=0,  x-7=0

or x=-3, x=2,  x=7

Using these critical points, we can divide number line into four sets:

[tex](-\infty,-3)[/tex], (-3,2), (2,7), [tex](7,\infty)[/tex]

We pick one number from each interval and plug into original inequality to see if that number satisfies the inequality or not.

Test for [tex](-\infty,-3)[/tex].

Clearly x=-4 belongs to [tex](-\infty,-3)[/tex] interval then plug x=-4 into [tex]\frac{x^2+x-6}{x-7}\leq 0[/tex]

[tex]\frac{(-4)^2+(-4)-6}{(-4)-7}\leq 0[/tex]

[tex]\frac{6}{-11}\leq 0[/tex]

Which is TRUE.

Hence [tex](-\infty,-3)[/tex] belongs to the answer.

Similarly testing other intervals, we get that only [tex](-\infty,-3)[/tex] and [tex](2,7)[/tex] satisfies the original inequality.

Hence final answer is [tex]x \leq -3[/tex] or [tex]2 \leq x<7[/tex]

correct choice is A because both ends are open circles.