Respuesta :

2(w+h)=perimeter
2((7x-5)+(5x+10))
1. Simplify
2(7x-5+5x+10)

2. Collect like terms
2((7x+5x)-5+10)

3. Simplify
2(12x-5+10)

4. Simplify 
2(12x+5)

5. Distribute
2*12x+2*5

6. Simplify
24x+2*5

7. Simplify 
24x+19

The perimeter of the rectangle is 24x+10, have a nice day :D