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Vectors and matrices — Question 6

QCAA 2021, Paper 2 · 1 mark

Q6 · 2021 · Technology-activeSimple familiar1 mark

QUESTION 6

The Cartesian equation of a sphere is given by x2+y2+z2+2x−2y=7x^2+y^2+z^2+2x-2y=7.
The centre and radius of the sphere are
(A)
(−1,1,0)(-1,1,0) and 33 respectively.
(B)
(−1,1,0)(-1,1,0) and 99 respectively.
(C)
(1,−1,0)(1,-1,0) and 33 respectively.
(D)
(1,−1,0)(1,-1,0) and 99 respectively.
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