What value of c makes x^2+6x+c a perfect square trinomial

Bernice paid $162 in interest on a loan of $1800 borrowed at 6%. how long did it take her to pay the loan off?

The vertices of a triangle are a(7.5), b(4,2), and c19. 2). what is

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document