我想問幾題 方程 數學題，不過所有都要 列式 !!
1.某長方形的長是闊的三倍，且其周界為24cm，求它的面積。
2.一條長36cm的鐵線圍成長方形，當中長比闊多2cm。
(a)求長方形的面積。
(b)若這條鐵路圍成另一個長為2cm的長方形，則長方形的面積是多少?
3.瑪莉,彼得和比提芬分享120枚郵票，其中彼得分得的是瑪莉的一半，而比提芬分得的是 彼得的三倍，問每人各分得郵票幾枚?!
4.媽媽給史提芬$250。他用了$45買魚，又買了一些每隻售$16的小龜。若他尚餘$45，問他買了多少隻小龜?
我想問幾題小六-中一方程數學題~急問
2007-09-01 5:01 am
回答 (2)
2007-09-01 5:39 am
✔ 最佳答案
1.let the length of the rectangular is 3xthe the width of the rectangular is x
3x+x+x+3x=24
8x=24
x=3
so the length of it is 9.
the area of it 3*9=27
2.let the width is x
the length is x+2
2(x+x+2)=36
2(2x+2)=36
4x+4=36
x=8
the length is 10
so the area of this rectangular is 80
若這條鐵路圍成另一個長為2cm的長方形
2x+2y=36
4+2y=36
y=16
the area of the new rectangular is 16*2=32
3.let mary has x units stamps
peter has y units stamps
and Beethoven has z units stamps.
x+y+z=120
y=x/2
z=3y =3(x/2)
sub these equations into x+y+z=120
x+x/2+3(x/2)=120
2x+x+3x=240
6x=240
x=40
mary has 40stamps
peter has 20stamps
and beethoven has 60
4.let he buys x turtle
250-45-16x=45
205-16x=45
-16x=x160
x=10
he buys 10 turtle
2007-09-01 5:24 am
1.設闊是X,長是闊的三倍,即長是3X
周界=(長+闊)x2
=(3X+X)x2
=4Xx2
=4Xx2=24
=24除2
=12
=12除4
X=3
∴闊係3
它的面積=3x3x3
=27CM(2)<--2次方
4.他買魚後剩餘的錢:250-45
=$205
他買小龜的數量:(205-45)除16
=160除16
=10隻
∴史提芬買了10隻小龜
周界=(長+闊)x2
=(3X+X)x2
=4Xx2
=4Xx2=24
=24除2
=12
=12除4
X=3
∴闊係3
它的面積=3x3x3
=27CM(2)<--2次方
4.他買魚後剩餘的錢:250-45
=$205
他買小龜的數量:(205-45)除16
=160除16
=10隻
∴史提芬買了10隻小龜
參考: 自己,,可惜只會做1&4....SOR丫..＞＜
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