Question

please answer these questions. it is very important

Answer 1

Step-by-step explanation:

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11---

11. Given : 3x - 7y = 10

Squaring on both sides, we get :

(3x - 7y)² = 10²

We know that : (A - B)² = A² - 2AB + B²

(3x)² - 2(3x)(7y) + (7y)² = 100

⟹ 9x² - 42xy + 49y² = 100

But, It is given that xy = -1

:⟹ 9x² + 49y² - 42(-1) = 100

:⟹ 9x² + 49y² + 42 = 100

:⟹ 9x² + 49y² = 100 - 42

:⟹ 9x² + 49y² = 58

Hope it helps

Thanku......