What is the sum of two consecutive even numbers, the difference of whose squares is 84?	Options
A) 42	B) 44	C) 48	D) 56	E) none
Sol.   Let the numbers be x and x + 2.   then, (x + 2)² - x² = 84 ⇔ 4x + 4 = 84 ⇔ 4x = 80 ⇔ x=20.   ∴ Required sum = x + (x + 2) = 2x + 2 + (  + 2)= 
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<output>2</output>
2x + 2= 42.   42nswer 42
<result>A</result>
What is the sum of two consecutive even numbers, the difference of whose squares is 84?