Question

if 3x-7y=10 and xy=-1 then the value of 9x2 +49y2

Answer 1

hello users ....
given equation is
3x - 7y + 10
and
xy= -1

solution:-
we have
3x -7y = 10
squaring on both sides
we get
(3x-7y)² = 10²
=> 9x² + 49 y² - 42 xy = 100
=> 9x² +49y² = 100 + 42(-1)
= 100 - 42 = 58 @nswer

⭐✡ hope it helps :)

Answer 2

Answer:

3x-7y=10

By taking power2both sides we get

(3x-7y)^2=10^2

9x^2+49y^2-42xy=100

9x^2+49y^2=100+42(-1)

100-42=58

This is your answer