Question

ME AJUDA NO EXÉRCICIO DE MATEMÁTICA

Answer 1

2x² + 5x = 3=0

( O = 3 e = 0 ficou estranho, mas ok.)

2x² + 5x - 3 = 0 

√Δ = b² - 4ac
√Δ = (5)² - 4 *(2)* (-3)
√Δ = 25 - (8) * - 3
√Δ = 25 - (24)
√Δ = 25 + 24
√Δ = 49
√Δ = 7

x = -b +/- √Δ / 2a
x = -5 +/- 7 / 2 * 2
x' = -5 + 7 / 4
x' = 2/4
x' = 1/2

x'' = -5 - 7/4
x'' =-12/4
x'' = -3

Letra B, 1/2 e -3

Um abraço!

Answer 2

2x² + 5x = 3

2x² + 5x - 3 = 0 


Δ = b² −4ac
Δ = (5)²−4⋅2⋅−3
Δ = 25 + 24
Δ = 49


$x = \dfrac{-b \pm \sqrt{\Delta}}{2*a}\\ \\ \\x = \dfrac{-5 \pm \sqrt{49}}{2*2}\\ \\ \\x = \dfrac{-5 \pm 7}{4}\\ \\ \\x' = \dfrac{-5 - 7}{4}\\ \\ \\x' = \dfrac{-12}{4}\\ \\ \\x' = -3\\ \\ \\x'' = \dfrac{-5 + 7}{4}\\ \\ \\x'' = \dfrac{2}{4}\\ \\ \\x'' = \dfrac{1}{2}$



$S = \{ -3, ~ \dfrac{1}{2}~ \}$