Question

11 If x + y = 8 and xy = 3, find the values of
(i) x-y
(ii) 3(x2 + y2 (iii) 5(x2 + y2) + 4(x – y).​

Answer 1

i) 8-3=5 is ans
ii) 15 raise to the power 2
iii) 6 raise to power 2
Hope it help you

Answer 2

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i) x - y = 7 [ from (3)]

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ii) 3(x² + y²)

= = 3 [(x + y)² - 2xy ]

= 3 [8²-2 × 15/4]

= 3 [ 64 - 15/2]

= 3 ( 128 - 15 )/2

= ( 3 × 113 )/2

= 339/2

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iii) = 5[ (x² + y²) + 4(x - y)]

= 5 [(x + y)² - 2xy ] + 4(x - y)]

= 5 [8²-2 × 15/4] + 4 × 7

= 5 [ 64 - 15/2 ] + 28

= 5 x 113/2+28

= 565/2 + 28

= (565 + 56 )/2

= 621/2.

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• I Hope it's Helpful My Friend.