Question

Calcule as equações abaixo

a)3x-4=5

b)2x²-6x-8=0

c)x²+x-12=0​

Answer 1

Resposta:

A) 3 x - 9 = 0

( 3 ) ⋅ x + ( - 9 ) = 0

x =- ( - 9 )3

x = -( 3 )⋅ ( - 3 )( 3 )= 3

B)2x2- 6 x - 8 = 0

( 2 ) ⋅x2+ ( - 6 ) ⋅ x + ( - 8 ) = 0

x =- ( - 6 ) ±( - 6 )2- 4 ⋅ ( 2 ) ⋅ ( - 8 )------------------√2 ⋅ ( 2 )

x =6 ±36 - ( - 64 )----------√4

x =6 ±100---√4

x =6 ± ( 10 )4

x1=164=( 4 )⋅ ( 4 )( 4 )= 4

x2=- 44=( 4 )⋅ ( - 1 )( 4 )= - 1

C)x2+ x - 12 = 0

( 1 ) ⋅x2+ ( 1 ) ⋅ x + ( - 12 ) = 0

x =- ( 1 ) ±( 1 )2- 4 ⋅ ( - 12 )-------------√2

x =- 1 ±1 - ( - 48 )---------√2

x =- 1 ±49--√2

x =- 1 ± ( 7 )2

x1=62=( 2 )⋅ ( 3 )( 2 )= 3

x2=- 82=( 2 )⋅ ( - 4 )( 2 )= - 4

ESPERO TER AJUDADO :)