After being rearranged and simplified, which of the following equations could
be solved using the quadratic formula? check all that apply.
a. 5x + 4 = 3x^4 - 2
b. -x^2 + 4x + 7 = -x^2 - 9
c. 9x + 3x^2 = 14 + x-1
d. 2x^2 + x^2 + x = 30

C and D

Step-by-step explanation:

The quadratic formula is

x= (-b±√b²-4ac)/2a

The formula uses the numerical coefficients in the quadratic equation.

The general quadratic equation is ax²+bx+c where a, b and c are the numerical coefficients

So, lets try and see;

A.

But due to the fact that  in this equation you have x⁴, the equation is not a quadratic equation thus can not be solved using this formula

B

C

D.

From the checking above, the equations will be C and D

.

step-by-step explanation: