Question

$\sqrt{x - 1} = 3 - x$
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Answer 1

(3-x)² = (√x-1)²

9-6x+x² = x-1

x² -7x +10= 0

∆ = 49-40= 9 => √∆=3

x = 7+3/2 = 5 {não serve)

x"= 7-3/2= 2 ✓ OK