Question

If x+y-z = 4 andx^2 +y^2 z^2 =30, then find the value of xy-yz-zx​

Answer 1

Answer:

xy-yz-zx=-7

Step-by-step explanation:

square of (x+y-z=4)

x^2+y^2+z^2+2xy-2yz-2xz=16

given y^2+x^2+z^2=30

30+2xy-2yz-2xz=16

2xy-2yz-2xz=-14

2(xy-yz-zx)=-14

xy-yz-xz=-7