Complete question is
Which of the following is a situation in which an equation cannot be solved using the quadratic formula? (a) The coefficient of the x^2-term is 1.
(b)The right-hand side of the equation is zero.
(c)One term of the polynomial has a degree of 3.
(d)The coefficient of the x-term is zero.
Answer :
(a) The coefficient of the x^2-term is 1 => we can use quadratic formula for any coefficient of x^2 term.
(b)The right-hand side of the equation is zero. => we can apply quadratic formula only when the right side of the equation =0
(c)One term of the polynomial has a degree of 3. => the highest degree of quadratic equation is 2. So we cannot apply quadratic formula for polynomial that has degree 3.
(d)The coefficient of the x-term is zero => we can apply quadratic formula but x^2 term should be there. 0 in x term does not affect the formula.
So answer is C