F.2 Maths question (onlyone)

樓上個2位都仲未搵到 A 同 B 既數值..

8Ax + 3Bx + 2B = 7x - 6
( 8A + 3B )x + 2B = 7x - 6

By comparing coefficients,
2B = -6
B = -3

8A + 3B = 7
8A + 3(-3) = 7
A = 2

Therefore, A=2 and B=-3

先搵a
(8A+3B)x+2B=7x-6
8Ax+3Bx+2B=7x-6
8ax = 7x- 6 -3bx-2b
a = 7x- 6 -3bx-2b
----------------------
8x
再搵b
(8A+3B)x+2B=7x-6
8Ax+3Bx+2B=7x-6
3bx+2b = 7x-6-8AX
3x+2(b) =7x-6-8AX
b= 7x-6-8AX
-------------
3x+2

2007-12-12 19:59:21 補充：
a=7x- 6 -3bx-2b ---------------------- 8x 即係a= 7x- 6 -3bx-2b 除 8x b= 7x-6-8AX ------------- 3x+2 即係b= 7x-6-8AX除3x+2

(8A+3B)x+2B=7x-6
8Ax+3Bx+2B=7x-6

THE FOLLOWING STEPS I DUN NOE LA.......
SORRY.........