Answer
Given in the question the equation
y = x² - 2x + 6
Name
a quadratic polynomial or a polynomial of degree 2
Ind. var
An input value of function is the independent value = x
Dep. var
The output value of function is the dependent value, as it depends on the value of the input = y
Rule
a function is a rule that assigns to each input exactly one output.
Evaluation
when x = -3
y = (-3)² - 2(-3) + 6
= 21