What is the complete factorization of r2 - 6r - 9s2 + 9?

If you had $1,900,000, how many days would it take you to spend all if you spent $1 a second. (there are 86,400 seconds in a day)

Determine the area of a triangle with (see picture below)

In a sale there is 25% of all prices a chair costs £45 in sale how much was it before the sale