In the diagram, B is a point on the y-axis. A(4 ; y), B, C(3 ; 0) and D(7 ; 6) are the vertices of rectangle ABCD. Diagonals BD and AC are drawn. The inclination of DC is a and BÂC =θ .
4.1 Determine the gradient of CD. (2)
4.2 Calculate the size of a. (2)
4.3 Determine the value of y. (2)
4.4 Calculate the size of θ. (5)
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