5.6X=17.28-4X
5.6X+4X=17.28
9.6X=17.28
X=17.28÷9.6
x =1.815X+3.8乘12=87.6希望你能帮我你好！
15x +3.8×12=87.6
15X=87.6-45.6
15x =42
X =42÷15
x =2.8谢谢你