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The operator $$\bigtriangleup$$ acts on two numbers to give the following outcomes:  $$3 \bigtriangleup 2 = 12$$  $$4 \bigtriangleup 5 = 40$$  $$5 \bigtriangleup 9 = 90$$  $$6 \bigtriangleup 1 = 12$$  What is $$2 \bigtriangleup 7$$ equal to? 
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The pattern of the operation is $$a \bigtriangleup b = a\times b\times2$$ 