1.	Which equation is in quadratic form?
		A.		B.	x4 - x2 + x - 1 = 0
		C.		D.	3x3 + 3x + 3 = 0
		Hint
	2.	Write the expression in quadratic form.
		A.		B.
		C.	cannot be done, since	D.
		Hint
	3.	Solve x4 – 625 = 0
		A.		B.
		C.	5, 5i	D.
		Hint
	4.	Which expression cannot be written in quadratic form?
		A.		B.
		C.		D.
		Hint
	5.	Solve
		A.	1, 1.22	B.
		C.		D.	1, 11.31
		Hint