The sum of the two digits of a number is 16. the number formed by reversing the digits is 18 more than the original number. determine the original number.

let t = the tens digit, u = the units digit, and u + t = 16. which of the following equations would complete the system?

9t - 9u = 18
9u - 9t = 18
tu = ut + 18

solve systems of equations by graphing. a system of linear equations contains two or more equations e.g. y=0.5x+2 and y=x-2. the solution of such a system is the ordered pair that is a solution to both equations. to solve a system of linear equations graphically we graph both equations in the same coordinate system