We need to find which of the following inequalities is equivalent to |m + 2| < 3Let's solve the problem using two methods
Method 1: SubstitutionWe will values in each option choice and plug in the question and check if it satisfies the question or not. ( Idea is to take such values which can prove the question wrong)
(A) m < 5Lets take m = 4 (which falls in this range of m < 5) and substitute in the equation |m + 2| < 3
=> |4 + 2| < 3
=> |6| < 3
=> 6 < 3 which is
FALSE(B) m < 1Lets take m = -10 (which falls in this range of m < 1) and substitute in the equation |m + 2| < 3
=> |-10 + 2| < 3
=> |-8| < 3
=> 8 < 3 which is
FALSE(D) m > -1Lets take m = 10 (which falls in this range of m > -1) and substitute in the equation |m + 2| < 3
=> |10 + 2| < 3
=> |12| < 3
=> 12 < 3 which is
FALSE(E) -5 < m < 1Lets take m = 0 (which falls in this range of -5 < m < 1) and substitute in the equation |m + 2| < 3
=> |0 + 2| < 3
=> |2| < 3
=> 2 < 3 which is
TRUESo,
Answer will be EMethod 2: AlgebraNow, we know that |A| < B can be opened as (Watch
this video to know about the
Basics of Absolute Value)
-B < A < B provided A is non negative
Assuming m+2 is non negative
-3 < m+2 < 3
Subtracting 2 from all the sides we get
-3-2 < m < 3-2
=> -5 < m < 1
So,
Answer will be EHope it helps!
Watch the following video to learn How to Solve Absolute Value Problems