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22 votes
If a+b=20 and ab=50
Then find the value of a^2+b^2​

2 Answers

8 votes

Answer:

a² + b² = 300

Explanation:

a + b = 20 ; ab = 50

(a +b)² = a²+ b² + 2ab

a² + b² + 2ab = (a + b)²

a² + b² + 2*50 = (20)²

a² + b² + 100 = 400

a² + b² = 400 - 100

a² + b² = 300

User Xnyhps
by
4.0k points
5 votes

Here,

a+b=20

ab=50

we know that,


\tt{ (a+b)^2=a^2+b^2+2ab }

According to the question,


\tt{(20)^2=a^2+b^2+2×50 }


\tt{ 400=a^2+b^2+100 }


\tt{ a^2+b^2=400-100 }


\tt{a^2+b^2=300 }

User Kvaps
by
4.6k points