If xy = 16 and x2 + y2 = 32, then the value of (x + y) is:

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If xy = 16 and x² + y² = 32, then the value of (x + y) is:

A±10

B±4

C±8

D±6

Answer:

Given:

x² + y² = 32 and xy = 16

Formula:

(x + y)² = x² + y² + 2xy

Calculation:

(x + y)²= x² + y² + 2xy

⇒ (x + y)² = 32 + 2 $\times$ 16

⇒ (x + y)² = 32 + 32

⇒ (x + y)² = 64

⇒ (x + y) = ±8

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