We know that each picture is equivalent to two books. For month 1, Toby had three pictures, each of them representing two books he read during this month. Therefore, number of books = 2*3 = 6 books
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If BA is d units the CB must be 2d units. B is on the x-axis, 2d units
right of C so its coordinates are (2d, 0). A is d units above B at (2d,
d). </span>