Question

$6x - 7 - x^{2} =1$

Answer 1

Explicação passo-a-passo:

- x² +6x -7 -1=0

- x² +6x -8=0 (×-1)

x² -6x +8=0

∆= (-6)² -4.1.8

∆= 36 - 32

∆= 4

x= -(-6)±√4/2.1

x= 6 ±2/2

x1= 6+2/2

x1= 8/2

x1=4

x2= 6-2/2

x2= 4/2

x2=2

S={ 2, 4}