1. p=3x+3y
a triangle is shown with 3 sides. on two of the sides it shows x+y. so it asks to find the measure of the third side of the triangle. p is the measure of the perimeter. show all work.

2. p=7x+2y
a triangle is shown with 3 sides. on one side, it says 2x+y. on the other, it says 3x-5y.

So the sum of two sides are 2x+2y and the perimeter is 3x+3y.  So if we subtract the two sides from the perimeter we will have the dimension of the final side

3x+3y-2x-2y=x+y which is the same as the other two sides, thus this is an equilateral triangle.

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Again we will subtract the sum of two sides from the perimeter to find the measure of the third side...

7x+2y-2x-y-3x+5y

2x+6y is the third side...