Question
Download Solution PDFIf a + b = 12 and 4ab = 140, then what is the value of a2 + b2?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven:
If a + b = 12 and 4ab = 140
Formula used:
(a + b)2 = a2 + b2 + 2ab
Calculation:
(a + b)2 = 122
⇒ 144 = a2 + b2 + 2ab
Since, 4ab = 140
⇒ ab = 35
⇒ 144 = a2 + b2 + 2 × 35
⇒ 144 = a2 + b2 + 70
⇒ a2 + b2 = 74
∴ The correct answer is option 2.
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