Ignoring the "?" in your question:

If the "?" is a squared symbol that wasn't caught:

Use the quadratic formula

to get the solutions:

as you can see, the discriminant is negative, so the equation has no solution.
Answer:
Step-by-step explanation:
1) Step 4: Marc has converted radical form to exponent form
Step 5: He has evaluated the value of the radical
3)
![x = \sqrt[3]{8}](https://tex.z-dn.net/?f=x%20%3D%20%5Csqrt%5B3%5D%7B8%7D)
Here, 3 is index and 8 is radicand.
Prime factorize 8 and for every 3 numbers we can take one number outside the radical
Solution:
![x = \sqrt[3]{2*2*2}\\\\x = 2](https://tex.z-dn.net/?f=x%20%3D%20%5Csqrt%5B3%5D%7B2%2A2%2A2%7D%5C%5C%5C%5Cx%20%3D%202)
4) No,my equation does not have an extraneous solution.
My solution, satisfies the equation
Answer:
ab= 7.8
ac= 6
bc=5
Step-by-step explanation:
1000 IS THE ANSWER EJN3;RVLGBPOIJGNTIOG;K