Find the center and the radius of the circle.x2 + y2 - 8x + 4y + 20 = 81

A. (-2, 4); r = 9
B. (2, -4); r = 81
C. (-4, 2); r = 81
D. (4, -2); r = 9


Answer: D

Mathematics

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Write the trigonometric expression as an algebraic expression containing u and v.cos(sin-1 u + cos-1 v)

A. uv - ()()
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C. v - u
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Find the direction the parabola opens, the coordinates of the vertex, the equation of the axis of symmetry and draw the graph.x = -(y + 1)2 + 6

A.
 
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B.
 
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C.

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axis of symmetry y = 6
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Evaluate the expression. + 

A.
B.
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