SAT数学题练习两道.

　　下面是两道数学题，都是关于几何方面的，大家可以在备考SAT数学考试的时候对此进行适当的练习。SAT数学题对于中国考生的作用，大部分都是用来熟悉题型和解答方法，而不是作为知识点的积累，所以大家在备考的时候，一定要抓住重点。

　　If triangle above is congruent to triangle (not shown), which of the following must be the length of one side of triangle ?

　　Answer Choices

　　(A)

　　(B)

　　(C)

　　(D)

　　(E) It cannot be determined from the information given.

　　The correct answer is D

　　Explanation

　　Triangle is congruent to triangle , so the lengths of the three sides of triangle are the same as the lengths of the three sides of triangle . Triangle is a - - triangle with hypotenuse of length , so the other two sides of triangle have lengths and . Therore, the lengths of the sides of triangle must be , , and . Of the choices given, only is one of these values.

　　If two sides of the triangle above have lengths 5and 6, the perimeter of the triangle could be which of the following?

　　. 　　. 　　.

　　Answer Choices

　　(A) only

　　(B) only

　　(C) only

　　(D) and only

　　(E) , , and

　　The correct answer is B

　　Explanation

　　Difficulty: Hard

　　In questions of this type, statements , , and should each be considered independently of the others. You must determine which of those statements could be true.

　　Statement cannot be true. The perimeter of the triangle cannot be , since the sum of the two given sides is without even considering the third side of the triangle.

　　Continuing to work the problem, you see that in , if the perimeter were , then the third side of the triangle would be , or . A triangle can have side lengths of , , and . So the perimeter of the triangle could be .

　　Finally, consider whether it is possible for the triangle to have a perimeter of . In this case, the third side of the triangle would be . The third side of this triangle cannot be , since the sum of the other two sides is not greater than . By the Triangle Inequality, the sum of the lengths of any two sides of a triangle must be greater than the length of the third side. So the correct answer is only.

　　以上就是这两道SAT数学题的全部内容，都是选择题型，来自SAT考试官方网站，后面附有详细的答案解析。大家可以在备考SAT数学考试的时候，根据自己的思考过程了解一些SAT数学考试中几何方面的知识。

更多SAT数学相关：

SAT数学练习题一道

6道SAT数学练习题

SAT数学练习题六道(代数)