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How do you solve #x^2 -2x ≤ 8#?

1 Answer

Aug 30, 2015

#-2<=x<=4#

Explanation:

Factorise the expression:

#x^2-2x-8<=0#
(x-4)(x+2)#<=#0
For this inequality to be true following two possibilities can exist:

i) #x-4>=0 and x+2<=0# (ii)#x-4<=0 and x+2>=0#

In the i) case , #x>=4 and x<=-2#, which is not possible.

In ii) case#x<=4 and x>=-2# is a feasible solution. The solution is therefore #-2<=x<=4#

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