Question

Qual resposta, preciso urgente

Answer 1

Explicação passo-a-passo:

1)

x² + x - 42 = 0

a= 1; b = 1; c = -42

Δ = b² - 4ac

Δ = 1² - 4 . 1 . (-42)

Δ = 1 + 168

Δ = 169

x = (-b ± √Δ)/2a

x = ( - 1 ± √169)/2 . 1

x = (-1 ± 13)/2

x' = (-1 + 13)/2

x' = (12)/2

x' = 6

x'' = (-1 - 13)/ 2

x'' = -14/ 2

x'' = -7

2)

x² - 5x + 6 = 0

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

Δ = b² - 4ac

Δ = (-5)² - 4 . 1 . 6

Δ = 25 - 24

Δ = 1

x = (-b ± √Δ)/2a

x = ( - (-5) ± √1)/2 . 1

x = (5 ± 1)/2

x' = (5 + 1)/2

x' = (6)/2

x' = 3

x'' = (5 - 1)/ 2

x'' = 4/ 2

x'' = 2

3)

x² - 8x + 12 = 0

a= 1; b = -8; c = 12

Δ = b² - 4ac

Δ = (-8)² - 4 . 1 . 12

Δ = 64 - 48

Δ = 16

x = (-b ± √Δ)/2a

x = ( - (-8) ± √16)/2 . 1

x = (8 ± 4)/2

x' = (8 + 4)/2

x' = (12)/2

x' = 6

x'' = (8 - 4)/ 2

x'' = 4/ 2

x'' = 2

S = {(2, 6)}

Raízes: 2 e 6

4)

x² + 7x + 12 = 0

a= 1; b = 7; c = 12

Δ = b² - 4ac

Δ = 7² - 4 . 1 . 12

Δ = 49 - 48

Δ = 1

x = (-b ± √Δ)/2a

x = ( - 7 ± √1)/2 . 1

x = (-7 ± 1)/2

x' = (-7 + 1)/2

x' = (-6)/2

x' = -3

x'' = (-7 - 1)/ 2

x'' = -8/ 2

x'' = -4

S = {(-4, -3)}

Raízes: -4 e -3