7(2X-6)=84,5(X-8)=3X,5.9X-9=4.2X+2.9,9(2X-3)-2=5(2X-1)

问题描述:

7(2X-6)=84,5(X-8)=3X,5.9X-9=4.2X+2.9,9(2X-3)-2=5(2X-1)

9 20 7 3

7(2X-6)=84
14X-42=84
14X=126
X=9
5(X-8)=3X
5X-40=3X
2X=40
X=20
5.9X-9=4.2X+2.9
1.7X=11.9
X=7
9(2X-3)-2=5(2X-1)
18X-27-2=10X-5
8X=24
X=3