Looking at the figure below, the four points of ABCD on the number axis correspond to integers. If the digit a corresponding to point a, point B corresponding to B, and b-2a = 7 So which of a, B, C, D is the origin on the number axis? Explain the reason__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |_____ → A B C D
B = a + 3; b-2a = 7, so a + 3-2a = 7 gets a = - 4, so C = a + 4 = 0
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