Question

If 3x-7y=10 and xy=-1 ,Find the value of 9x²+49y²,and this answer is 58 but how can solve it ?​

Answer 1

Step-by-step explanation:

1. from xy=-1, we take y=-1/X

and then substitute y in another equation

There we get the value of x as 1 and 7/3

Sub X values in xy=-1 we get y value

substitute those X and y in 9X^2+49y^2