It is known that a, B and C are the three sides of △ ABC, and B + C-B + b-c-a + C-A-B is simplified Could you be more detailed? Thank you! ER.. Excuse me? dial the wrong number.. B + C-A + b-c-a + c-a-b.. Sorry...

It is known that a, B and C are the three sides of △ ABC, and B + C-B + b-c-a + C-A-B is simplified Could you be more detailed? Thank you! ER.. Excuse me? dial the wrong number.. B + C-A + b-c-a + c-a-b.. Sorry...

a. B and C are the three sides of △ ABC,
a+c>b====>a+c-b>0,b-c-ac====>c-a-b

(3x+12)/4=2-(5x-7)/3
Find x

Take 12 on both sides
3(3x+12)=24-4(5x-7)
9x+36=24-20x+28
20x+9x=24+28-36
29x=16
x=16÷29
x=16/29

It is known that 3 (5x + 2) + 5 ＜ 4x-6 (x + 1) is reduced to | 3x + 1 | - | 1-3x |

Remove brackets to get 15x + 6 + 5 ＜ 4x-6x-6, transfer to get 15x-4x + 6x ＜ - 6-6-5, merge to get 17x ＜ - 17, coefficient to 1 to get x ＜ - 1, | 3x + 1 | - | 1-3x | = - (3x + 1) - (1-3x) = - 3x-1-1 + 3x = - 2

28 / 69 × 23 / 35 + 4 / 5 × 7 / 8 3 / 4x-4.5 = one and half 1 / 3x-1 / 5x = 6 x by 1 / 3 by 4 / 5 = 8 2 / 3x-1 / 4x = 1

1、28/69×23/35＋4/5×7/8
=4/15+7/10
=8/30+21/30
=29/30
2. 3 / 4x-4.5 = one and a half
0.75x-4.5=1.5
0.75x=6
x=8
3、1/3x-1/5x=6
（5/15-3/15）x=6
2x/15=6
x=6÷2/15
x=45
4. X times 1 / 3 times 4 / 5 = 8
x×1/2×4/5=8
2x/5=8
x=8÷2/5
x=20
5、2/3x-1/4x=1
（2/3-1/4）x=1
（8/12-3/12）x=1
5x/12=1
x=1÷5/12
x=2.4