Toán Lớp 8: 1/(x-4) ²-(x-2)(x+2)=6 2/4(x-3) ²-(2x-1)(2x+1)=10 3/9(x+1) ²-(3x-2)(3x+2)=10

Question

Toán Lớp 8:  1/(x-4) ²-(x-2)(x+2)=6 2/4(x-3) ²-(2x-1)(2x+1)=10 3/9(x+1) ²-(3x-2)(3x+2)=10

hiennhi98 · Answer

Của bn đ&acirc;y. Xin lỗi chữ mik hơi xấu. Ch&uacute;c bạn học tốt!!

thanhmaianh · Answer

$a, (x - 4)&sup2; - (x - 2)(x + 2) = 6$   $&harr; x&sup2; - 8x + 16 - (x&sup2; - 4) - 6 = 0$   $&harr; x&sup2; - 8x + 16 - x&sup2; + 4 - 6 = 0 $   $&harr; 14 - 8x = 0$   $&harr; 8x = 14$   $&harr; x =  frac{7}{4}$   $b, 4(x - 3)&sup2; - (2x - 1)(2x + 1) = 10$   $&harr; 4(x&sup2; - 6x + 9) - (4x&sup2; - 1) - 10 = 0$   $&harr; 4x&sup2; - 24x + 36 - 4x&sup2; + 1 - 10 = 0$   $&harr; 27 - 24x = 0$   $&harr; 24x = 27 $   $&rArr; x =  frac{9}{8}$   $c, 9(x + 1)&sup2; - (3x - 2)(3x + 2) = 10$   $&harr; 9(x&sup2; + 2x + 1) - (9x&sup2; - 4) - 10 = 0$   $&harr; 9x&sup2; + 18x + 9 - 9x&sup2; + 4 - 10 = 0$   $&harr; 18x + 3 = 0$   $&harr; 18x = -3$   $&rArr; x =  frac{-1}{6}$      $ text{Bn tham khảo}$   $@ Sun$