Rút gọn vế trái:
VT = (12x – 5)(4x – 1) + (3x – 7)(1 – 16x)
= 12x.(4x – 1) + (–5).(4x – 1) + 3x.(1 – 16x) + (–7).(1 – 16x)
= 12x.4x+ 12x.(–1) + (–5).4x + (–5).(–1) + 3x.1 + 3x.(–16x) + (–7).1 + (–7).(–16x)
= 48x2 – 12x – 20x + 5 + 3x – 48x2 – 7 + 112x
= (48x2 – 48x2) + (– 12x – 20x + 3x + 112x) + (5 – 7)
= 83x – 2
Vậy ta có:
83x – 2 = 81
83x = 81 + 2
83x = 83
x = 83 : 83
x = 1.
Tìm x, biết
(12x-5) (4x-1)+(3x-7) (1-16x)=81
Tìm x, biết:
( 12x - 5 )( 4x - 1 ) + ( 3x - 7 )( 1 - 16x ) = 81
tìm x biết
1. 5x( 1 - 2x ) - 3x( x + 18 ) = 0
2. (12x - 5)* (4x - 1) + ( 3x - 7) * ( 1 - 16x ) = 81
13. tìm x biết:
(12x - 5) (4x - 1) + (3x - 7) (1 - 16x) = 81
giúp mk nhé!!
tìm x :
( 12x - 5 ) ( 4x - 1 ) + ( 3x - 7 ) ( 1 -16x ) =81
Tìm x, biết:
( 12x - 5 )( 4x - 1 ) + ( 3x - 7 )( 1 - 16x ) = 81
giải chi tiết luôn nha
tìm x
(12x-5)(4x-1)+(3x-7)(1-16x)=81
xin mk với đang vội
tim x pik
(12x-5)*(4X-1)+(3X-7)*(1-16X)=81
Tìm x, y biết a) 3y(2y-40)-2y(3y+5)=44
b)(12x-5)(4x-1)+(3x-7)(1-16x)=81
