五題數學題

1.１５＋（ｘ－２）=８－（２＋ｘ）
13 + x = 6 - x
2x = -7
x = -3.5

2.（ｘ－３）／４　=６＋ｘ
x - 3 = 24 - 4x
5x = 27
x = 5.4


3.ｕ／４＋２.５ 　=ｕ／６＋３
3u + 30 = 2u + 36
u = 6

4.　-ｘ／３＋５／６=（２ｘ－５）４
-2x + 5 = 24(2x - 5)
-2x + 5 = 48x - 120
50x = 125
x = 2.5


5.４（ｘ＋１）－２（ｘ－１）=３（ｘ－２）
4x + 4 - 2x + 2 = 3x - 6
2x + 6 = 3x - 6
x = 12

1)15+(x-2)=8-(2+x)
15+x-2=8-2-x
13+x=6-x
2x=-7
x=-3.5

2)(x-3)/4=6+x
x-3=24+4x
-27=3x
-9=x

3)u/4+2.5=u/6+3
6u+3u=4u+2.5u
9u=6.5u
15.5u=0
u=0

4)-x/3+5/6=(2x-5)4 <---------------------先乘除後加減
-x/3 + 5/6=8x-20
-2x/6 + 5/6=8x-20
(-2x+5)/6=8x-20
-2x+5=48x-120
46x=-125
x=-0.368

5)4(x+1)-2(x-1)=3(x-2)
4x+4-2x+2=3x-6
2x+6=3x-6
12=x

1. -3.5
2. -9
3. 6
4. 2.5
5. 11