1. а) (3x +4) /(x² -16) -x² /(x² -16) =0
3x +4 -x² =0, *(-1)
x² -3x -4 =0
D =b² -4ac(a=1, b= -3, c= -4)
D =9 +16 =25 =5²
x1 =(3 -5)/2 = -1
x2 =(3+5)/2 =4
ответ: x = -1; x =4
b) (3x +8(x -5)) /x(x -5) =2
3x +8x -40 =2x(x -5)
11x -40 =2x² -10x
-2x² +11x +10x -40 =0, *(-1)
2x² -21x +40 =0
D =441 -4*2*40 =441 -320 =121 =11²
x1 =(21 -11)/4 =2.5
x2 =(21+11)/4 =8
ответ: x =2.5; x =8