y is in the plane if the 3 vectors are linearly dependant.

iff their determinant is 0

A=`det([[1,-2,h],[0,1,-3],[-2,7,-5]])` =0

iff `A=det([[1,-2,h],[0,1,-3],[0,3,-5+2h]])` =0

A=`det([[1,-3],[3,-5+2h]])=-5+2h+9=2h+4` =0

**Answer h=-2**

y is in the plane if the 3 vectors are linearly dependant.

iff their determinant is 0

A=`det([[1,-2,h],[0,1,-3],[-2,7,-5]])` =0

iff `A=det([[1,-2,h],[0,1,-3],[0,3,-5+2h]])` =0

A=`det([[1,-3],[3,-5+2h]])=-5+2h+9=2h+4` =0

**Answer h=-2**