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|2𝑥 + 4| = 8

 

2|𝑥| + 4 = 8

 

|𝑥 + 1| = 0

Guest Mar 27, 2017
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|2x +4| = 8       Technique is to always square both sides and solve the quadratic

(2x+4)^2 = 64

4x^2 +16x +16 = 64          divide through by  4

x^2 +4x +4 =16

x^2 +4x - 12= 0

(x+6)(x-2) = 0    so x = -6  and x = 2

 

2|x| +4 =8    rearrange to get the modulus expression on its own,and,again,square both sides

2|x| = 4     so |x| =2      so x^2 =4     so x= plus or minus 2

 

Exactly the same method for the last one.Have a try yourself.

Guest Mar 27, 2017

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