Can someone please help me with this absolute value inequality, can I draw a graph for it? |(x+4)/(x+2)|<=1x+4x+21?

1 Answer
Mar 27, 2018

(-oo,-3](,3]

Explanation:

|(x+4)/(x+2)|<=1x+4x+21

We know by the absolute value property that we have to solve both:

(x+4)/(x+2)<=1x+4x+21 and -((x+4)/(x+2))<=1(x+4x+2)1

For:

(x+4)/(x+2)<=1x+4x+21

Subtract 11

(x+4)/(x+2)-1<=0x+4x+210

Add LHS:

((x+4)-(x+2))/(x+2)<=0(x+4)(x+2)x+20

Simplify:

2/(x+2)<=02x+20

Divide by 2:

1/(x+2)<=01x+20

There is no solution for zero, (undefined division by zero)

only x<-2x<2

For:

-((x+4)/(x+2))<=1(x+4x+2)1

Subtract 1:

-(x+4)/(x+2)-1<+0x+4x+21<+0

Multiply by -11:

(x+4)/(x+2)+1<=0x+4x+2+10

Add LHS:

(2x+6)/(x+2)<=02x+6x+20

Solving for zero:

(2x+6)/(x+2)=02x+6x+2=0

x=-3x=3

We now need to look at :

|(x+4)/(x+2)|-1<=0x+4x+210

For:

x<-3x<3

0<=|(x+4)/(x+2)|<10x+4x+2<1

So:

|(x+4)/(x+2)|-1<=0x+4x+210

For x> -3x>3, x!=-2x2

|(x+4)/(x+2)|>1x+4x+2>1

So:

|(x+4)/(x+2)|-1>0x+4x+21>0

So only: x<=-3x3

Solution set:

(-oo,-3](,3]