Question

x²+x-20=0 cálculo e resultado​

Answer 1

Resposta:

x² + x - 20 = 0

a = 1, b = 1, c = - 20

∆ = b² - 4.a.c

∆ = 1² - 4.1.(-20)

∆ = 1 - 4.(-20)

∆ = 1 + 80

∆ = 81

x = - b ± √∆ / 2.a

x = - 1 ± √81 / 2.1

x = - 1 ± 9 / 2

x' = - 1 - 9 = (-10) ÷ 2 = - 5

x'' = - 1 + 9 = 8 ÷ 2 = 4

x' = - 5

x" = 4

Answer 2

a=1

b=1

c=-20

∆=b^2-4×a×c

∆=1^2-4×1×(-20)

∆=1+80

∆=81

x= -b±√∆/2×a

x= -1±√81/2×1

x= -1±9/2

x'= -1+9/2= 8/2=4

x"= -1-9/2= -10/2= -5

S= {4 , -5}