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# If a – b = 3 and a2 + b2 = 29, find the value of a + b ?a)±6b)±7c)±4d)±3Correct answer is option 'B'. Can you explain this answer? Related Test: Quantitative Aptitude - Test 1

## SSC Question

 VIHAAN SAURABH Oct 09, 2019
As per the given data,
⇒ a – b = 3
Squaring on both sides, we get
⇒ a2 + b2 - 2ab = 9
⇒ 29 – 2ab = 9
⇒ 29 – 9 = 2ab
⇒ 20 = 2ab
⇒ ab = 10
We know that (a + b)2 = a2 + b2 + 2ab
⇒ (a + b)2 = 29 + 2(10) = 49
⇒ a + b = √49 = ±7
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