Решить систему уравнений:

а) у-2 х=2, 5x^2 - y = 1

б) х-2 у^2=2, 3x+y=7

A) y=2+2-x

y = (4-x)

5x^2-4+x-1=0

5x^2+x-5=0

D=1^2-4*5 * (-5) = 1+100=101=√101

x1 = (-1+√101) / 2*5 = (-1+10,05) / 10=9,05/10

x1=0,905

x2 = (-1-10,05) / 10 = (-11,05) / 10

x2=-1,105

y1 = (4-x1) = (4-0,905)

y1=3,095

y2 = (4-x2) = (4 - (-1,105)) = 4+1,105

y2=5,105

б) y = (7-3x)

x-2 (7-3x) ^2=2

x-2 (49-42x+9x^2) = 2

x-98+84x-18x^2=2

18x^2-85x+100=0

D = (-85) ^2-4*18*100=7225-7200=25=5^2

x1 = (- (-85) + 5) / 2*18=90/36

x1=2,5

x2 = (- (-85) - 5) / 36=80/36

x2=20/9

y1 = (7-3x1) = (7-3*2,5) = 7-7,5

y1=-0,5

y2 = (7-3x2) = 7-3 (20/9) = 7-20/3 = (21-20) / 3

y2=1/3