Question

Obtenha os pontos comuns aos graficos de : a) y=x²+2x e y = x+2 ; b) y=x²-4x e y= x/2 ; c) y= x²-8x+12 e y = 2x +3

Answer 1

Oi

a) 

x² + 2x = x + 2
x² + x - 2 = 0

d² = 1 + 8 = 9
d = 3

x1 = (-1 + 3)/2 = 2/2 = 1, y1 = 3
x2 = (-1 - 3)/2 = -4/2 = -2, y2 = 0

b)

x² - 4x - x/2 = 0

2x² - 8x - x = 0

2x² - 9x = 0

x*(2x - 9) = 0

x1 = 0, y1 = 0
x2 = 9/2, y2 = 9/4

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