Respostas

2014-07-07T09:04:55-03:00
A=10 b=21 c=-10
Δ= b^{2} -4.a.c
Δ=( 21)^{2} -4.10.-10
Δ=441+400

 x_{1} = \frac{-21+29}{2.10} = \frac{8}{20} = \frac{2}{5} =841
 x_{2} =\frac{-21-29}{2.10}= \frac{-50}{20} =  -\frac{5}{2}


  • Usuário do Brainly
2014-07-07T09:28:37-03:00
10x² + 21x - 10 = 0
Δ = b² - 4 . a . c
Δ = 21² - 4 . 10 . (- 10)
Δ = 441 + 400
Δ = 841

x = (- b ± √Δ)/(2 . a)
x = (- 21 ± √841)/(2 . 10)
x = (- 21 ± 29)/20

x' = (- 21 + 29)/20
x' = 8/20
x' = 2/5

x'' = (- 21 - 29)/20
x'' = - 50/20
x'' = - 5/2

S = {- 5/2, 2/5}