請(qǐng)問(wèn),這幾道有關(guān)于一元一次方程的題目做對(duì)了嗎?
一：4X+3(2X-1)=71+(X-5)
4X+6X-3=71X-355
4X+6X+71X=355-3
81X=352
X=4.35(用四舍五入法,只要小數(shù)點(diǎn)后兩位的數(shù))
二：6(X+3)=2.5(X-3)
6X+3=2.5X-1.2
6X+2.5X=3-1.2
8.5X=1.8
X=0.21(用四舍五入法,只要小數(shù)點(diǎn)后兩位的數(shù))
三：5X+(2-4X)=0
5X+2-4X=0
5X+4X=2
9X=2
X=0.22(用四舍五入法,只要小數(shù)點(diǎn)后兩位的數(shù))
四：10X-4(3X+3)=12+(X-7))
10X-12X+12=12X-84
10X-12X-12X=-84-12
-14X=-96
X=-6.86(用四舍五入法,只要小數(shù)點(diǎn)后兩位的數(shù))
五：4X+3(2X+1)=70-(X+6)
4X+6X+3=70X+420
4X+6X-70X=420-3
-60X=417
X=-6.95
六8X-3(3X+2)=6
8X-9X+6=6
X=-1