PLZ HELP WILL GIVE BRAINLST

Use the Quadratic Formula to find the exact solutions of x2 + 7x − 4 = 0.

x equals negative b plus or minus the square root of b squared minus 4 times a times c, all over 2 times a

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?