单选题
What is the perimeter of triangle PQR?
A.
B.
C. 15
D. 25
E.
A.
B.
C. 15
D. 25
E.
【正确答案】
B
【答案解析】By the Pythagorean theorem, you calculate (PR)
2
=5
2
+5
2
=50, thus
. The perimeter is thus
. The perimeter is thus