Final answer:
The equation provided is not quadratic given the presence of an x^4 term and thus, cannot be solved using the quadratic formula as provided. The student will need to correct the equation to a standard quadratic form (ax^2 + bx + c = 0) before we can solve for x.
Step-by-step explanation:
The student's question regarding the value of x in the quadratic equation x4 + 4x = -18 seems to be misstated. Typically, a quadratic equation is in the form ax2 + bx + c = 0. However, the equation provided is not quadratic (as it includes an x4 term) and appears incorrect as written. If it is meant to be quadratic, we would need the correct form of the equation to apply the quadratic formula to find the solutions for x.
We can attempt to correct the equation. If we assume the equation should be x2 + 4x + 18 = 0, we could then apply the quadratic formula. The standard quadratic formula is x = [-b ± √(b2 - 4ac)] / (2a). However, without the correct equation, we cannot proceed with finding the correct value of x.