选择题
2019 AMC 8 Problem 21: Triangle from Three Lines
What is the area of the triangle formed by the lines y = 5, y = 1 + x, and y = 1 − x?
2019 AMC 8 第21题：三线三角形
由直线 y = 5、y = 1 x 和 y = 1 − x 形成的三角形的面积是多少
A.
4
B.
8
C.
10
D.
12
E.
16