TOÁN 9 | PHƯƠNG TRÌNH | CN 15/6/2025

Answer explanation

(x-1)(x-2)=0

x-1=0 -> x = 1

x-2=0 -> x=2

Answer explanation

(x-1)(x-2) +(x-1)(x+3)=0

(x-1)(x-2+x+3)=0

(x-1)(2x+1)=0

x=1 hoặc x = -1/2

Answer explanation

Bài mẫu gợi ý:

x^2-4x+3=0

x^2-3x-x+3=0

x(x-3)-(x-3)=0

(x-3)(x-1)=0

x=3 hoặc x=1

Answer explanation

bài mẫu:

1/x + 1/(9 - x) = 1/2

• ĐK: x ≠ 0 và 9 - x ≠ 0 => x ≠ 9

• 2(9 - x) + 2x = x(9 - x)

• 18 - 2x + 2x = 9x - x²
  18 = 9x - x²

• x² - 9x + 18 = 0

• (x - 3)(x - 6) = 0

• x - 3 = 0 => x = 3 (TM)

• x - 6 = 0 => x = 6 (TM)

Answer explanation

|x-1|=5

TH1: x-1=5 => x=6

TH2: x-1=-5 => x=-4

Answer explanation

|3x-1|=|-2x-3|

TH1: 3x-1=-2x-3 => 5x=-2 => x=-2/5

TH2: 3x-1=2x+3 => x=4

Answer explanation

|x-1|=5x

DK: x >=0

TH1: x-1=5x => -4x=1 => x=-1/4 (L)
TH2: x-1=-5x => 6x=1 => x=1/6 (TM)