)+4-7*-4 what is the answer to this equation?

What are the solutions of the equation x4 + 6x2 + 5 = 0? use u substitution to solve.

The price of a visit to the dentist is \$50$50. if the dentist fills any cavities, an additional charge of \$100$100 per cavity gets added to the bill. if the dentist finds nn cavities, what will the cost of the visit be?

The measures of ? 1, ? 2, and ? 3 are 40%, 12.5%, and 25% of the sum of the angle measures of the quadrilateral. find the value of x.