Question

三角形地块 $ACD$ 位于 Aspen Road、Brown Road 和一条铁路之间。Main Street 为东西方向，铁路为南北方向。图中的数字表示距离，单位为英里。铁路轨道的宽度可以忽略。地块 $ACD$ 的面积是多少平方英里？

The triangular plot of $ACD$ lies between Aspen Road, Brown Road and a railroad. Main Street runs east and west, and the railroad runs north and south. The numbers in the diagram indicate distances in miles. The width of the railroad track can be ignored. How many square miles are in the plot of land $ACD?$

$2$

$3$

$4.5$

$6$

$9$

答案：C

知识点：三角形面积

难度评级：900

解答：

三角形 $ADC$ 的底边是 $CD$ ，长度为 $3$ 。高也是 $3$ 。

因此 $ADC$ 的面积为 $\dfrac{1}{2} \cdot 3 \cdot 3 = 4.5$ 。

所以正确答案是 C。

The base of $ADC$ is $CD,$ which is $3.$ The altitude is $3$ as well.

Therefore, the area of $ADC$ is $\dfrac{1}{2} \cdot 3 \cdot 3 = 4.5.$

Thus, C is the correct answer.

2009 AMC 8 第 7 题

答案：C

难度评级：900

解答：

其他年份的第 7 题