Algebra & Equations · Question 21 · Medium
If x + y = 12 and xy = 35, what is the value of x² + y²?
- 74
- 109
- 214
- 144
Answer and explanation
Answer: A. 74
Explanation: x² + y² = (x + y)² − 2xy = 144 − 70 = 74. (Indeed x and y are 5 and 7.)
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