Which of the following functions is not written in explicit form? y=x x^2-6xy-9y^2=0 y=0 y=-squrt (1-x2)

Option 2 and 3 are not written in explicit form.

Step-by-step explanation:

We have four functions we have to find which one of them are not written in explicit form:

Explicit form is the form in which we can finc the value of n.

Option 1 is correct

y=x because

we can calculate y and x by substituting different values.

Option 2 is incorrect because we can not calculate y from the given equation

Option 3 is incorrect because y=0 we can not find anything.

Option 4 is correct because we can find values of y   by substituting different values of x in the given equation that is .