Question

Please answer this. Very urgent. I will mark you as Brainliest.

Answer 1

Step-by-step explanation:

see attached file for your answer

Answer 2

Correct question:

1. If x + y = 11 and xy = 18, find (x - y)

Given:

• x + y = 11
• xy = 18

To find:

• (x - y) = ?

Method:

Using (x - y)² = x² + y² - 2xy

⇒ (x - y)² = x² + y² + 2xy - 4xy

⇒ (x - y)² = (x + y)² - 4xy

⇒ (x - y)² = (11)² - 4×18

⇒ (x - y)² = 121 - 72

⇒ (x - y)² = 49

⇒ (x - y) = √49

⇒ (x - y) = ± 7

For next question,

Given:

• x - y = 2√3
• xy = 1

To find:

• x + y = ?

Method:

(x + y)² = x² + y² + 2xy

⇒ (x + y)² = x² + y² - 2xy + 4xy

⇒ (x + y)² = (x - y)² + 4xy

⇒ (x + y)² = (2√3)² + 4×1

⇒ (x + y)² = 12 + 4

⇒ (x + y)² = 16