a×a+b×b=400,4a-4b=16 then find a and b?
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Answer :
a = 16, b = 12
Solution :
a² + b² = 400 ----- eq 1
4a - 4b = 16
a - b = 4
a = 4 + b
consider eq 1
Substitute a = 4 + b in eq 1
(4 + b)² + b² = 400
16 + b² + 8b + b² = 400
2b² + 8b + 16 = 400
b² + 4b + 8 = 200
b² + 4b - 192 = 0
b² + 16b - 12b - 192 = 0
b(b + 16) - 12(b + 16) = 0
(b + 16)(b - 12) = 0
b = -16 or b = 12
We consider positive number i.e, b = 12
a = 4 + b = 16
∴ a = 16, b = 12
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