Question

x-y=4
x²+y²=40
resolver por delta

Answer 1

Olá Vivic

x - y = 4
x² + y² = 40

y = x - 4
y² = x² - 8x + 16 

x² + x² - 8x + 16 = 40

2x² - 8x - 24 = 0 

x² - 4x - 12 = 0

delta
d² = 16 + 48 = 64
d = 8

x1 = (4 + 8)/2 = 12/2 = 6 
x2 = (4 - 8)/2 = -4/2 = -2

y = x - 4

y1 = 6 - 4 = 2
y2 = -2 - 4 = -6 

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