Hello!
The answer is:
The third side measure is: 4x+y
Why?
We must remember that the perimeter of a triangle is equal to the sum of all of its three sides, so, using the given information, we have:
[tex]Perimeter=a+b+c=8x+4y\\a=x+2y\\b=3x+y\\c=?[/tex]
So, we can calculate the measure of the third side using the following equation, and grouping the like terms, so:
[tex]8x+4y=x+2y+3x+y+c\\c=8x+4y-x-2y-3x-y\\c=8x-x-3x+4y-2y-y\\c=8x-4x+4y-3y\\c=4x+y[/tex]
Have a nice day!
