If x + y = 10 and xy = 21, what are the values of x and y?
Category: Math · Difficulty: expert
Hint: Use the quadratic formula.
Answer
x = 7, y = 3
Explanation
Rearranging gives x and y as roots of t² - 10t + 21 = 0. Solving gives x = 7, y = 3.
This is a expert math riddle — one of the harder riddles here. The answer is x = 7, y = 3.
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