1題中一既代數應用題(20分!!!!!!!)(急!!!!!!!!!!!!!)

5x+x=108
6x=108
x=108/6
=18
3年之後就再+3
姐係21

Let the age of Emily be x.
The age of Emily's father now is 5x (5 times as old as she) +3 (Three years ago)
(5x+3) + x = 108
5x + 3 + x = 108
5x + x + 3 = 108
6x + 3 = 108
6x = 108 - 3
6x/6 = 105/6
x = 17.5
Emily is 17.5 year-old at the moment

2007-10-29 15:32:43 補充：
首先,要弄清現狀.問題問Emily's age俾既TIPS係the sum ...108於是搵Emily's age同Emily's father ageEmily's age係unknown於是要let Emily's age be [[variable]]再搵Emily's father age[[5 times as old as she]] 5X (三年前)要知道現在 5X (三年前) 3 (三年前,距離多少年相對就加多少year-old)

Let emily be x.
5x+3=108
5x=105
x=21
Emily now is 21 years old!

p+5p=108