載入中... 相關課程 Back 一元方程式的應用題 (英) 登入觀看 ⇐ Use this menu to view and help create subtitles for this video in many different languages. You'll probably want to hide YouTube's captions if using these subtitles. 一元方程式的應用題 (英) : 一元方程式的應用題 上傳學習單 下載學習單 相關課程 0 / 750 The perimeter of Tina's rectangular garden is 60 feet. If the length of the garden is twice the width - the length is twice the width - what are the dimensions of the garden? So, let's draw this garden here: Tina's garden. So it's a rectangle - they tell us that it's a rectangular garden - So, it looks something like this. And let's say that this is the width. So if this is the width, then this is also going to be the width. And this is the length up here. And they tell us that the length of the garden is twice the width. So, if this is w, then the length is going to be 2w. It's going to be twice the width. This is also going to be 2w over here. Now, what's the perimeter of this garden? Well, it's going to be w+w+2w+2w - let me write this down - The perimeter of this garden is going to be w+2w+w+2w, which is equal to what? This is w plus 2w is 3w - 4w, 6w. So this is equal to 6w. That's the perimeter in terms of the width. They also tell us that the actual numerical value of the perimeter is 60 feet - it is 60 feet. So, this perimeter 6w must be equal to 60 if we're assume that we're dealing with feet. So, we just have the equation 6w=60. We can divide both sides of this equation by 6, so that we have just a w on the left hand side. 6w divided by 6 is just w and then 60 divided by 6 is 10. So, we have w=10. So this, the width of the garden is 10. So, this distance over here is 10. And then, what is the length of the garden? Well, it's two times the width. So, this is equal to 20. The length is equal to 20. And so, we're done. This is a 20 by 10 garden.