单选题If the point (-1, 2) is on a graph that is symmetric with respect to the y-axis, then which of the following points must also be on the graph?A(1, 2)B(-1, -2)C(1,-2)D(-2, 1)E(2, -1)
单选题
If the point (-1, 2) is on a graph that is symmetric with respect to the y-axis, then which of the following points must also be on the graph?
A
(1, 2)
B
(-1, -2)
C
(1,-2)
D
(-2, 1)
E
(2, -1)
参考解析
解析：
If (a, b) is a point on a graph symmetric with respect to they-axis, then (-a, b) is also on the graph. (1, 2) is the reflection of the point (-1, 2) over the y-axis.
If (a, b) is a point on a graph symmetric with respect to they-axis, then (-a, b) is also on the graph. (1, 2) is the reflection of the point (-1, 2) over the y-axis.
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