Verified answer

Explicação passo-a-passo:

I)

(2x-3).(x+4)-8x = 10

2x²+8x-3x-12-8x= 10

2x² -3x-12-10= 0

2x²-3x-22= 0

a=2; b = -3; c = -22

∆= b²-4ac

∆= (-3)²-4.2.(-22)

∆= 9+8.22

∆= 9+176

∆= 185

x = (-b+/- √∆)/2a

x = [-(-3)+/-√185)/2.2

x = (3+/-√185)/4

R :

x ' = (3-√185)/4

x " = (3+√185)/4

185:5

37:37

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Raízes

II)

x²+6x= 5+3x

x²+6x-3x-5=0

x²+3x-5= 0

a=1; b = 3; c = -5

∆= b²-4ac

∆= 3²-4.1.(-5)

∆= 9+20

∆= 29

x = (-b +/- √∆)/2a

x = (-3+/-√29)/2.1

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R.:

x' = (-3+√29)/2

x' = (-3+√29)/2x " = (-3-√29)/2

III)

x²+3x+2=0

a=1; b = 3; c= 2

raízes

∆= b²-4ac

∆= 3²-4.1.2

∆= 1

x = (-b+/- √∆)/2a

x = (-3+/-1)/2

x '= (-3-1)/2= -4/2= -2

x " = (-3+1)/2= -2/2= -1

IV)

x²+3x+2= 0

a,b,c= ?

∆= ?

a=1; b = 3; c =2

∆= b²-4ac

∆= 3²-4.1.2

∆= 9-8

∆= 1

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v)

1x²-5x+6= 0

x²-5x+6= 0

a=1; b = -5; c = 6

∆= b²-4ac

∆= (-5)²-4.1.6

∆= 25-24

∆= 1

x = (-b +/- √∆)/2a

x = (5+/-1)/2.1

x '= (5+1)/2=6/2= 3

x" = (5-1)/2= 4/2= 2