Question

If x +y = 14 and x - y = 6, then the product of 2
and y is equal to which of the following?

Answer 1

40

Explanation:

x+y=14

x-y=6

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x=-y+14

x-y=6

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Substitute:

-y+14-y=6

-2y+14=6

-2y=-8

y=4

x=-y+14

x=-4+14

x=10

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4•10=40