Question

7x ao quadrado+x+2 igual 0 ? e x ao quadrado -7x igual -12 ? urgente

Answer 1

7x² + x + 2 = 0
Δ = b² - 4ac = 1² - 4 x 7 x 2 = 1 - 56 = - 55

Δ < 0 
$S=\O$
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x² - 7x - 12 = 0
Δ = b² - 4ac = (- 7)² - 4 x 1 x (- 12) = 49 + 48 = 97

x = (- b - √Δ)/2a = (7 - √97)/2
x = (- b + √Δ)/2a = (7 + √97)/2