There are two equations here, and you can use substitution to solve.
Let L equal the length & W equal the width.
The equation for perimeter is L + W + L + W or 2L + 2W so our first equation is 2L + 2W = 35
The problem tell us the second equation also: the...

The way you will set this question up is key. This will be a substitution formula and there will be two equations.
Let C equal the number of children and A equal the number of adults.
The two equations are:
A + C = 285 {the number of adults + the number of children = the...