Question

if x+y=7 by2 and xy=5by2;find:(i)x-y​

Answer 1

Answer:

Given,

x+y=

2

7

,xy=

2

5

we know, (x+y)

2

−(x−y)

2

=4xy

=>(

2

7

)

2

−(x−y)

2

=4×

2

5

=>(

4

49

)−(x−y)

2

=

2

20

=>−(x−y)

2

=

2

20

−

4

49

=>−(x−y)

2

=

4

40−49

=>−(x−y)

2

=−

4

9

=>x−y=

4

9

=>x−y=±

2

3