If a^2−b^2=848 and a^2+b^2=5650 then what is the value of 11ab?

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27 Dec 2017 Find the Value

If a^2−b^2=848 and a^2+b^2=5650 then what is the value of 11ab?

OPtion

1) 3249
2) 2401
3) 30123
4) 3097
5) 3079
6) 30273
7) 30723
8) 32499
9) 34299
10) None of these

Solution

As per question
a^2 - b^2 = 848 ...(1)
a^2 + b^2 = 5650...(2)

Adding (1) and (2), we get
2a^2 = 6498
=> a^2 = 3249
=> a = 57

Substracting (1) from (2), we get
2b^2 = 4802
=> b^2 = 2401
=> b = 49

11*a*b= 11*57*49 = 30723

Correct Option: 7 Best Solution (0)