How do you solve #x^2>=36# using a sign chart?

1 Answer
Aug 3, 2016

Answer:

# x in(oo,-6]uu[6,oo)#

Explanation:

#x^2>=36#

Let us take the equation first .

#x^2=36#

#x=+-6#

Divide the number line into 3 parts , use this x valuesenter image source here
Check which interval satisfies the inequality #x^2>=36#
In the interval # (-oo,-6) # choose a point say x=-7
x^2=49 so x^2>=36#

In the interval #(-6,6) , x=0,x^2=0 , x^2<36#
in the interval #(6,oo) , x=7 , #x^2=49 , #x^2>=36#
enter image source here

First and 3rd interval satisfies the inequality . we have >=

# x in(oo,-6]uu[6,oo)#