解方程:
x+3x=12.6;????????
x÷0.3=6.8;?????????
x-12.5=12.5.
网友回答
解:(1)x+3x=12.6,
?????????? 4x=12.6,
????????4x÷4=12.6÷4,
??????????? x=3.15;
(2)x÷0.3=6.8,
x÷0.3×0.3=6.8×0.3,
????????? x=2.04;
(3)x-12.5=12.5,
x-12.5+12.5=12.5+12.5,
????????? x=25.
解析分析:依据等式性质:(1)先化简,再在方程两边同时除以4求解,(2)方程两边同时乘0.3求解,(3)方程两边同时加12.5求解.
点评:本题主要考查学生依据等式性质解方程能力.