MATH F.1

你可用下面方法,

[because] 3x-11=2x+1
3x-2x=11+1
x=12
[so]The length of the rectangle is:
3x12
=36cm

在以上方程,3x cm=長方形的長, 而(2x+1) cm則=長方形的闊,如果長方形的長比長方形的闊長11cm, 那麼 長-11=闊[即 3x-11=2x+1] 就能找出x了, 再把答案x3就能找出長方形的長了。

The length of the rectangle is 3x cm and the width is (2x+1) cm.If the length is 11 cm longer than the width, Find the length of the rectangle.

3x - (2x + 1) = 11

3x - 2x -1 = 11

3x - 2x = 11 + 1

x = 12


x = 12

The length of the rectangle is 3x

3(12)
=36

The length of the rectangle is 36 cm

代入:

x= 12

The length is 3x = 3(12) = 36

The width is (2x+1) = 24+1 = 25

The length is 11 cm longer than the width

36 - 25

= 11 cm

Correct
圖片參考：http://tw.yimg.com/i/tw/ugc/rte/smiley_4.gif
!

3x-(2x+1)=11
3x-2x-1=11
x=11+1
x=12
since the length of the rectangle is 3x cm & x=12
therefore the length of the rectangle=3(12)=36cm

If the length is 11 cm longer than the width,
so, 3x - (2x+1) = 11
3x - 2x - 1 = 11
x = 10cm