2.Given that x+y=39 and x:y=4:9
(a) For the expression x:y = 4:9 , express x in terms of y
(b) Hence , find the values of x and y
痳煩大家幫幫我，詳列步驟及計算方法。謝謝，無言感激!!!!
更新1:
第一題應該是Given that (a+2): (a+5):b =3:4:7. Find the values of a and b.
數學問題~急~
2007-06-10 6:41 am
1.Given that (a+2) :b =3:4:7. Find the values of a and b.
2.Given that x+y=39 and x:y=4:9
(a) For the expression x:y = 4:9 , express x in terms of y
(b) Hence , find the values of x and y
痳煩大家幫幫我，詳列步驟及計算方法。謝謝，無言感激!!!!
2.Given that x+y=39 and x:y=4:9
(a) For the expression x:y = 4:9 , express x in terms of y
(b) Hence , find the values of x and y
痳煩大家幫幫我，詳列步驟及計算方法。謝謝，無言感激!!!!
回答 (2)
2007-06-10 6:52 am
✔ 最佳答案
1.你係咪打漏左 d 野..(a+2):b = 3:4:7 (有三個數??)2a)
x:y=4:9
x/y = 4/9
x = 4y/9
2b)
x+y=39
(4y/9)+y=39
4y+9y = 39*9 (成條式乘 9)
13y = 351
y = 27
2007-06-12 15:16:58 補充：
(a 2): (a 5):b =3:4:7ie. (a 2)/(a 5) = 3/4, (a 2)/b = 3/7 & (a 5)/b = 4/74(a 2) = 3(a 5)4a 8 = 3a 15a = 7(a 2)/b = 3/7(7 2)/b = 3/79*7 = 3bb = 21Therefore, a = 7 & b = 21.
參考: me
2007-06-10 6:55 am
1)
(a+2) :b =3:4:7
左邊兩個比又點會等於右邊三個比
打少左野
2a)
x/y = 4/9
x = 4y/9
b)
4y/9 + y = 39
(4/9 + 1) y = 39
(13/9) y = 39
y = 27
x = 12
(a+2) :b =3:4:7
左邊兩個比又點會等於右邊三個比
打少左野
2a)
x/y = 4/9
x = 4y/9
b)
4y/9 + y = 39
(4/9 + 1) y = 39
(13/9) y = 39
y = 27
x = 12
收錄日期: 2021-04-23 21:58:38
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