If a – b = 5 and ab = 12, find the value of a2 + b2.

1.	If a – b = 5 and ab = 12, find the value of a2 + b2.
Answer» a – b = 5, ab = 12 Squaring, a – b = 5, both sides, (a – b)² = (5)² a² + b² – 2ab = 25 a² + b² – 2 x 12 = 25 a² + b² – 24 = 25 a² + b² = 25 + 24 a² + b² = 49

Answer»

a – b = 5, ab = 12

Squaring, a – b = 5, both sides,

(a – b)² = (5)²

a² + b² – 2ab = 25

a² + b² – 2 x 12 = 25

a² + b² – 24 = 25

a² + b² = 25 + 24

a² + b² = 49

Discussion

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