Answer:
112
Explanation:
It appears that the relation is f(a, b) = a(a+b).
f(3, 4) = 3(3+4) = 21
f(2, 5) = 2(2+5) = 14
f(7, 7) = 7(7+7) = 98
f(8, 6) = 8(8+6) = 112
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The symbol "+" has apparently been repurposed from its usual meaning in math. It is being used as an infix operator with two arguments. We have shown the relation above as a function f with two arguments (a, b). In our definition ...
f(a, b) = a(a+b)
the symbol "+" has its usual meaning.
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Additional comment
This sort of question requires a little bit of "out of the box" thinking. It helps immensely if you're familiar with your addition and multiplication facts. Then you are in a position to recognize how the outputs may be related to the inputs.