Question

if a+b=9 and ab=10 find the value of a²+b²

Answer 1

a+b = 9 and ab = 10

a²+b² = (a+b)² - 2ab
= 9² - 2(10)
= 81 - 20
= 61

Answer 2

Answer:

a²+b²=61

Step-by-step explanation:

Given a+b=9 ---(1)

ab = 10 ---(2)

On Squaring equation (1) , we get

(a+b)² = 9²

=> a²+b²+2ab=81

=> a²+b²+2×10=81 /*From (1)

=> a²+b²+20 = 81

=> a²+b² = 81-20

=> a²+b² = 61

Therefore,

a²+b² = 61

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