donut 發問時間： 社會與文化語言 · 9 年前

英文數學問題4題

express y as a function of x

1. y=3xy+5

solve each equation or inequality

2. x+3x=4x

3. x-0.04(x-10)=96.4

4. the perimeter of a rectangle is 84 meters. if the width is 16 meters less than the length, then what is the width of the rectangle?

2 個解答

• 9 年前
最佳解答

express y as a function of x

1. y=3xy+5

y-3xy= 5

(1-3x)y =5

y=5/(1-3x)

solve each equation or inequality

2. x+3x=4x

4x = 4x

3. x-0.04(x-10)=96.4

x-0.04x+0.4=96.4

0.96x=96

x=100

4. the perimeter of a rectangle is 84 meters. if the width is 16 meters less than the length, then what is the width of the rectangle?

The width of the rectangle is 13 meters.

• heidi
Lv 7
9 年前

1.

y-3xy=5

(1-3x)y=5

y=5/(1-3x)

2.

4x=4x

0x=0

x為任意數

3.

x-0.04x+0.4=96.4

0.96x=96

x=100

4.

設length為x

width為x-16

2[x+(x-16)]=84

x+(x-16)=42

2x-16=42

2x=58

x=29

width為29-16=13