Question

if x+y=5 and xy=4 then x-y is​

Answer 1

Answer:

xy = 4 ......(i)

x + y = 5.....(ii)

On squaring eqⁿ (ii) both sides;

( x + y )² = (5)²

⇒ x² + y² + 2xy = 25

⇒ x² + y² + 2 * 4 = 16

⇒ x² + y² = 25 - 8

⇒ x² + y² = 17

Now, we know that ;

(x - y)² = x² + y² - 2xy

⇒ (x - y)² = 17 - 2 * 4

⇒ (x - y)² = 17 - 8

⇒ ( x - y)² = 9

⇒ x - y = √9

⇒ x - y = 3

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Answer 2

Answer:

Step-by-step explanation:

hope it helps.....