方程的一些题,快

题目

方程的一些题,快

心算
5x  + 12x =         19a  -  8a  =             5.7b  + 6.2b =
16x  -  2x  =        32a  +  9a =             8.3b  -  5.2b =
20.3t  +  12.5t  =            4.3x  -  2.1x =          7.5a  - 3.4a =
 
x 丶x  =            4a  × 5 =              6a  +    5a   =

       12y  + 8y =        3x × 0 =       &

答案

心算5x + 12x =17x 19a - 8a = 11a 5.7b + 6.2b =11.9b16x - 2x = 14x 32a + 9a = 41a 8.3b - 5.2b =3.1b20.3t + 12.5t =32.8t 4.3x - 2.1x =2.2x 7.5a - 3.4a =4.1ax 丶x = 4a × 5 = 20a 6a + 5a =11a12y + 8y =20...