3times a number is 4 less than the square of that number. find the negative solution

In a rectangle klmn, km = 6x + 16 and ln = 49. find the value of x

Einstein office equipment has a rental plan for office machines. a fax machine that lists for $722.98 can be rented for 22% of the price annually. the state imposes a usage charge of 3.2%. if stephen hawking travel decides to rent the fax machine, what will its total monthly rental charge be?

Ratio of circumference to diameter example plz i need to now what it looks like.