Question

11. mx - ny = m2 + n2
x + y = 2m by cross multiplication method​

Answer 1

Answer:

mx−ny=

m 2

n 2

(i)x+y=

2m⟶

(ii)

On simplification,

mx−

ny−

(m

2

+n

2

) =

0x+y−

2m=

0

On cross multiplication,

∣

∣

∣

∣

∣

∣

−n

1

− (m

2

+n

2

)

−2m

∣

∣

∣

∣

∣

∣

x

=

∣

∣

∣

∣

∣

∣

m

1

− (m

2

+n

2

)

−2m

∣

∣

∣

∣

∣

∣

−y

=

∣

∣

∣

∣

∣

∣m

1−n

1∣

∣

∣

∣

∣

∣

1

⇒

∣2mn+m

2

+n

2

∣

x

=

∣−2m

2

+m

2

+n

2

∣

−y

=

m+n

1

∴x=

m+n

(m+n) 2

=

m+

n

y=

m+n

(m

2

−n

2

)

=

m−

n