Question

a) √2x+5=√x+8 b) √3x-2=5 c) 3 √x=12 d) √x2+3x-9=x me ajudem irracional, com a conta junta...

Answer 1

A) √2x+5=√x+8

 (√2x+5)² = (√x+8 )²  ==>  2x + 5 = x + 8

2x - x = 8 - 3 ==> x = 5
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b) √3x-2=5 ==>  √2x = 5 +2

(√2x)² = 7² ==> 2x = 49 

x = 49/2
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c) 3√x=12 ==> (3√x)² =12²

9x = 144 ==> x = 144/9

x = 16
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