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Y^2 - x^2 = 0
y + 3x = 4

y = 4 - 3x
y^2 - x^2 = 0 

(4 - 3x)^2 - x^2 = 0 *
16 - 24x + 9x^2 - x^2 = 0 
8x^2 - 24x + 16 = 0   /:8
x^2 - 3x + 2 = 0 
D = 9 - 8 = 1
x1 = ( 3 + 1)/2 = 4/2 = 2
x2 = ( 3 - 1)/2 = 2/2 = 1

x1 = 2
y1 = 4 - 3x1 = 4 - 6 = - 2

x2 = 1
y2 = 4 - 3x2 = 4 - 3 = 1

Ответ
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