All linear relations are functions
The quadratic equations can be a function if we restrict the domain of it
The given relations are
This is a linear relation, then it is a function, we can put it in the form
This is a linear relation, then it is a function
This is a linear relation, then it is a function, we can put it in the form
We will put it in the form of y as a subject
To find y we will take square root for both sides
That means each value of x has 2 values of y, then
This can not be a function