中一英文數學練習方程式

1) Let x be the number of stickers in the smaller group.
let y be the number of stickers in the bigger group.
x+y=60............(1)
7x=3y................(2)
(1) x 7,
7x+7y= 420..........(3)
(3)-(2),
7x+7y-7x=420-3y
7y=420-3y
10y=420
y=42
sub y=42 into (1)
x+42=60
x=18
the number of stickers in the smaller group is 18.



2) Let x be the score Edward gained.
Let y be the score William gained.
x+y=6500...........(1)
2y-1300=x............(2)
From(1),
x=6500-y.........(3)
sub (3) into (2),
2y-1300=6500-y
3y=7800
y=2600
Sub y=2600 into (1),
x+2600=6500
x=3900
Edward gained 3900 points.



BTW, this might not be form one maths :P form 2 ga

2012-11-17 19:51:57 補充：
我大過你一年:)))))))))))))))))))))))))))))))))))))))))))))))))

2012-11-18 10:46:46 補充：
Edward gets1300 points LESS THAN TWO TIMES WILLIAM'S SCORE:
EDWARD 拎到的分數比WILLIAM的2倍少1300分
because Edward gets→1300 points less than(少過) two times william's score
SO, 2y=x+1300 or 2y-1300=x

1.Let x be the number of stickers in the smaller group.

7x=3(60-x)
7x=180-3x
7x+3x=180
10x=180
x=180÷10
x=18

1.Edward將60張貼紙分成兩堆 一堆較多 一堆較
少的那堆的七倍等於多的那堆的三倍
列式：
設兩堆為x y
x+y=60
7x=3y
x=18
y=42