Hello sir/madam.
I would appreciate if you could explain quadratic equations​

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

Melanie is buying a bathing suit that costs 39.99. she is given a discount at the cash register of $6.00 when she scratched 15% off on a game piece for a store promotion. what will the sale price of melanie’s bathing suit be?

What is the cube root of -1,000p^12q3? -10p^4 -10p^4q 10p^4 10p^4q