Answer
Choices B and C
Work Step by Step
Quadratic equations take the form $ax^2+bx+c=0.$ In particular, the highest exponent of the variable is $2.$ Thus, Choice A ($x+2=0$) and Choice D ($x^3+x^2+4=0)$ are not quadratic equations because the highest exponent of the variable is not $2$.
Choice B ($x^2-8x+16=0$) and Choice C $(2t^2-5t=3)$ are quadratic equations because the highest exponent of the variable is $2$.
