Question

x²+5x=9 calcule por favor ​

Answer 1

Resposta:

x²+5x=9

x²+5x +25/4 -25/4=9

x²+5x+(5/2)² =9+25/4

(x+5/2)²=36/4+25/4

(x+5/2)²=61/4

x+5/2 =±√(61/4)

x'=-5/2 +√61/2     e  x'' = -5/2 -√61/2  

Answer 2

Resposta:

S = {$\frac{-5 + \sqrt{61} }{2} , \frac{-5-\sqrt{61} }{2}$}

x² + 5x = 9

x² + 5x - 9 = 0

Δ = 5² - 4. 1 (-9)

Δ = 25 + 36

Δ = 61

x' = [-5 + √61]/2.1 ∴ x ' = $\frac{-5+\sqrt{61} }{2}$

x'' = $\frac{-5 - \sqrt{61} }{2}$