. trình (hs khá) a) (2x – 5) 2 – (x + 2) 2 = 0 b) (3x 2 + 10x – 8) 2 = (5x 2 – 2x + 10) 2 c) (2x + 7) 2 = 9(x + 2) 2 d) 4(2x + 7) 2 = 9(x + 3) 2 e) 3x 2 + 2x – 1 = 0 f) x 2 – 5x + 6 = 0 PHẦN. Khá) a) 4x )11x (2 2x 3 x2 2x 2 − − = − − + − b) 2x 1x 1x 1x 2xx 1x 1x 2 −− − + = + −+ − + − c) 1x 4 1x 1x 1x 1x 2 − = + − − − + d) )5x(6 7 x250 15 )5x(4 3 2 + −= − + − e) x84 x81 3x6 x2 )x41(3 x8 2 2 + + − − = − f) 9x 6 7x2 1 )7x2)(3x( 13 2 − = + + +− PHẦN. 0: a) 3x – 2 = 2x – 3 b) 3 – 4y + 24 + 6y = y + 27 + 3y 2. Giải các phương trình sau bằng cách đưa về dạng ax + b = 0: a) 5 – (x – 6) = 4(3 – 2x) b) 2x(x + 2) 2 – 8x 2 = 2( x – 2) (x 2 + 2x + 4)