Which Answer Is a Rectangular Form of the Given Polar $r = 18 \cos \theta$

question 15

Multiple Choice

Which answer is a rectangular form of the given polar equation?
$r = 18 \cos \theta$

• A) \(( x - 9 ) ^ { 2 } + y ^ { 2 } = 81\)
• B) \(( x + 9 ) ^ { 2 } + y ^ { 2 } = 81\)
• C) \(( x + 9 ) ^ { 2 } + y ^ { 2 } = 9\)
• D) \(x ^ { 2 } + ( y + 9 ) ^ { 2 } = 81\)
• E) \(x ^ { 2 } + ( y - 9 ) ^ { 2 } = 81\)

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