g) 30 – 3(x – 2) = 18
h) 5(x – 6) – 2(x + 3) = 12
k) 3(x – 4) – (8 – x) = 12
l) 4(x – 5) – 3(x + 7) = -19
k) 7(x – 3) – 5(3 – x) = 11x – 5
l) 7(x – 9) – 5(6 – x) = -6 + 11x
g) 30 – 3(x – 2) = 18
h) 5(x – 6) – 2(x + 3) = 12
k) 3(x – 4) – (8 – x) = 12
l) 4(x – 5) – 3(x + 7) = -19
k) 7(x – 3) – 5(3 – x) = 11x – 5
l) 7(x – 9) – 5(6 – x) = -6 + 11x
`g) 30 – 3(x -2) = 18`
`→30-3x+6=18`
`→36-3x=18`
`→3x=18`
`→x=6`
Vậy `x=6`
` h) 5(x – 6) – 2(x + 3) = 12`
`→5x-30-2x-6=12`
`→3x-36=12`
`→3x=48`
`→x=16`
Vậy `x=16`
`k) 3(x – 4) – (8- x) = 12`
`→3x-12-8+x=12`
`→4x=12+12+8`
`→4x=32`
`→x=8`
Vậy `x=8`
` l) 4(x – 5) – 3(x + 7) = -19`
`→4x-20-3x-21=-19`
`→x=-19+20+21`
`→x=22`
Vậy `x=22`
`k) 7(x – 3) – 5(3 -x) = 11x – 5`
`→7x-21-15+5x=11x-5`
`→12x-36=11x-5`
`→12x-11x=-5+36`
`→x=31`
Vậy `x=31`
` l) 7(x – 9) – 5(6 – x) = -6 + 11x`
`→7x-63-30+5x=-6+11x`
`→12x-93=-6+11x`
`→12x-11x=-6+93`
`→x=87`
Vậy `x=87`
Đáp án:
Giải thích các bước giải:
g) $30 – 3(x – 2) = 18$
$30 – 3x + 6 = 18$
$3x = 36 – 18$
$3x = 18$
$x = 6$
h) $5(x – 6) – 2(x + 3) = 12$
$5x – 30 – 2x – 6 = 12$
$3x – 36 =12$
$3x = 48$
$x = 16$
k) $3(x – 4) – (8 – x) = 12$
$3x – 12 – 8 + x = 12$
$4x = 32$
$x = 8$
l) $4(x – 5) – 3(x + 7) = -19$
$4x – 20 – 3x – 21 = -19$
$x – 41 = -19$
$x = 22$
k) $7(x – 3) – 5(3 – x) = 11x – 5$
$7x – 21 – 15 + 5x – 11x = -5$
$x – 36 = -5$
$x = 31$
l)$ 7(x – 9) – 5(6 – x) = -6 + 11x$
$7x – 63 – 30 + 5x – 11x = -6$
$x – 93 = -6$
$x = 87$