Question

Resolva as equações a seguir:


A) 2x+4x-10=70

B)X2+X-6=0

C)3X+4X-2X=100

D)2X2+4x=0

Answer 1

Vamos lá

Calculo:

Resolvendo a letra A

2X + 4X - 10 = 70

2X + 4X = 70 + 10

6X = 80

X = 80 / 6

X = 40 / 3

Resolvendo a letra B

X² + X - 6 = 0

Δ = b² - 4 • a • c

Δ = ( 1 )² - 4 • 1 ( - 6 )

Δ = 1 + 24

Δ = 25

X = - b ± √ Δ / 2 • a

X = ( - 1 ± √ 25 ) / 2 • 1

X = ( - 1 ± 5 ) / 2

X1 = - 1 + 5 / 2 = 4 / 2 = 2

X2 = - 1 - 5/ 2 = - 6 / 2 = - 3

S { 2 , - 3 }

Resolvendo a letra C

3X + 4X - 2X = 100

7X - 2X = 100

5X = 100

X = 100 / 5

X = 20

Resolvendo a letra D

2X² + 4X = 0

X ( 2X + 4 ) = 0

X ( X + 2 ) = 0

X1 = 0

2X - 4 = 0

2X = 0 + 4

2X = 4

X = 4 / 2

X = 2

S { 0 , 2 }