A) 4X(5X + 2) - (10X - 3)(2X + 7) = 133 ;B) 3(6X - 5)(4X + 1) - (8X + 3)(9X - 2) = 203

9. Tìm x, biết:

a) 4x(5x + 2) - (10x - 3)(2x + 7) = 133 ;

b) 3(6x - 5)(4x + 1) - (8x + 3)(9x - 2) = 203.