pre cal I need to know how to solve the inequality or system

pre cal. I need to know how to solve the inequality or system using any method. answers in interval notation or ordered pair

y=x4 Xa_3y2 +1870 3xa_xy : 3 4 9-%(1-x) +y 7 9 M)

1) y = x +9

14x^2 + y^2 = 81

Substituting equation 1 in 2nd euqtation:

14x^2 + (x+9)^2 = 81

14x^2 + x^2 +81 +18x =81

15x^2 +18x =0

x( 15x +18) =0

x =0 ; x= -18/15 = -6/5

Now corresponding y values : y = x+9 = 9 ; y = -6/5 +9 = (-6 +45)/5 = 39/5

2) x^2 -3y^2 = -18 ----(1)

4x^2 +y^2 = 45 -----(2)

Just multiply equ. (1) by 4

4x ^2 -12y^2 = - 72

4x^2 +y^2 = 45

------------------- subtract

-13y^2 = - 117 -----> y^2 = 9 -----> y = +/- 3

x^2 -3y^2 = -18------> x^2 -3(9) = -18

x^2 = 27 -18 = 9 -----> x = +/-3

x = +/-3 ; y = +/- 3

4) 9 -8 ( 1-x) < =6

Subtract 9 from both sides:

9 -9 -8(1-x) < = 6-9

-8(1-x) < = -3

8(1-x) >=3

1-x > = 3/8 ---> x < = 1-3/8

x< = 5/8

Solution :( - inf, 5/8 ]