25+5x=39+3x怎么解方程,3(2x-3)+15=7(x-1)怎么解方程快x10000000000000000000000000谢谢

问题描述:

25+5x=39+3x怎么解方程,3(2x-3)+15=7(x-1)怎么解方程
快x10000000000000000000000000谢谢

25+5x=39+3x
5x-3x=39-25
2x=14
x=7
3(2x-3)+15=7(x-1)
6x-9=7x-7
7x-6x=-9+7+15
x=13

25+5x=39+3x
2x=14
x=7
3(2x-3)+15=7(x-1)
6x-9+15=7x-7
x=13


25+5x=39+3x
-->5x-3x=39-25 (方程左右移动)
-->2x=14
-->x=7

3(2x-3)+15=7(x-1)
--> 6x-9+15=7x-7 (去括号)
--> 6x-7x= -7-15+9
--> -x=-13
-->x=13