簡單的一元一次方程,help me plz^^”

2(a+1)+3a=17
2a+2x1+3a=17
5a+2=17
5a=17-2
5a=15
a=15/5
a = 3

2(a+1)+3a=17
2(1)+2a=17
2a=15
a=7.5

by ME!

2(a+1)+3a=17
2a+2+3a=17
5a+2=17
5a=15
a=3

2(a+1)+3a=17
2a+a+3a=17 <-- 先柝括號2(a+1) =2 x a + 2 x 1 = 2a+a
6a=17 <--移項
a=17/6,, 等如17除6

2009-11-29 16:11:47 補充：
2(a+1)+3a=17
2a+２+3a=17 <-- 先柝括號2(a+1) =2 x a + 2 x 1 = 2a+２
５a=15 <--移項
a=3,,

2(a+1)+3a=17
2a+2+3a=17
5a=17-2
5a/5=15/5
a=3
唔知正唔正確&gt;.&lt;