Решите систему неравенств х+у = -7 х^2+у^2 = 25

Question

Решите систему неравенств

х+у = -7

х^2+у^2 = 25

Answer 1

x+y=-7

x^2+y^2=25

 

 

x=-7-y

(-7-y)^2+y^2=25

49-2*-7*-y+ 2y^2=25

-14y  +  2y^2+24=0

 2y^2-14y+24=0

y^2-7y+12=0

y=-3

y=-4

x= -4

x=-3 

 

 

Answer 2

X = - 7 - Y

(-7 - Y)^2 + Y^2 = 25

-(7 +Y)^2 + Y^2 = 25

- Y^2 - 14Y - 49 +Y^2 = 25

- 14Y = 25 + 49

- 14Y = 74

Y = - 5 2\7

X = - 7 + 5 2\7 = - 1 4\7