Which equation represents a quadratic function?

a. y=3x²+1
b. y=3x+1
c. y-x=3²
d. x-y²=2

Quadratic functions also referred to:
a. Quadratic equation
b. parabolic equation
c. parabolic function
d. linear function

The general form of a function is:
a. ax²+bx+c=0
b. y=ax²+bx+c
c. y=a(x-h)²+k
d. y=ax+b

the one-to-one relation is called:
a. linear function
b. linear equation
c. quadratic function
d. quadratic equation

the two-to-one relation is called:
a. linear function
b. linear equation
c. quadratic funtion
d. quadratic equation​