Question

me ajudem porfaaaaaa​

Answer 1

2x²+x-3=0

a=2 b=1 c=-3

∆=1- 4•2•-3

∆= 25

x= -b±√∆/2a

x=-1±5/4

¹ x= -1 +5 /4

x= 4/4

x=1

²x=-1-5/4

x=-6/4

x= -3/2

soluções 1 e -3/2

-3x²+18x-15=0

a= -3 b=18 c=-15

∆=18²- 4.(-3). -15

∆=324 -180

∆=144

x= -18±√144/2.-3

x=-18 ±12/-6

x¹=-18+12/-6

x= -6/-6

x=-1

x²=-18-12/-6

x= -30/-6

x= 5

soluções 5 e -1

espero ter ajudado

Answer 2

Resposta:

1)

2x²+x-3=0

$x = \dfrac{-\,b \pm \sqrt{b^{2} - 4ac} }{2a} = \dfrac{-\, 1 \pm \sqrt{1^{2} - 4\times 2 \times (-3)} }{2 \times 2 } = \dfrac{-\, 1 \pm \sqrt{1 + 24} }{4 } = \dfrac{-\, 1 \pm \sqrt{25} }{4 } = \dfrac{-\, 1 \pm5 }{4 }$

$x_1 = \dfrac{ -1 + 5}{5} = \dfrac{4}{4} = 1\\\\x_2 = \dfrac{-1 - 5}{4} = \dfrac{- 6}{4} = -\, \dfrac{3}{2}$

2)  - 3x² + 18x -15 = 0 $\div$ $(-\, 3)$

  x²- 6x + 5 = 0     fatorando para calcular a raiz

(x - 5)(x - 1) = 0

(x - 5) = 0

x - 5 = 0

x' = 5

(x - 1) = 0

x -1 = 0

x" = 1