Решите систему уравнений:

a) {x-2y-4=0

{x^2-2y^2=16

б) {2x+y=3

{x^2+y^-6y=36

{x-2y-4=0

x^2-2y^2=16

x=2y+4

(2y+4) ^2-2y^2=16

2y^2+16y=0

y (2y+16) = 0

y1=0 2y=-16

y = - 8 x1=0+4=4; x2 = 2 * (-8) + 4 = - 12

б) {2x+y=3

x^2+y^2-6y=36

y=3-2x

x^2 + (3-2x) ^2 - 6 (3-2x) = 36

x^2+9-12x+4x^2-9-12x=36

5x^2 - 24x-36=0

D=36^2

x1 = (24+36) / 10=6

x2 = (24-36) / 10 = - 1.2

y1=3-2*6 y2=3 - (-1.2) * 2

y1=-9 y2=5.4