The difference between two numbers is 13.Twice the smaller plus three times the larger is 129.Find the value of the larger number.
+310 Let x and y be our two numbers, with y > x. Write two equations.
y - x = 13
3y + 2x = 129
Multiply the first equation by 2.
2y - 2x = 26
Add this to our second equation to get
5y = 155
y = 155/5 = 31
