Answer:
10+2x
Step-by-step explanation:
A rectangle has 4 sides. Two pairs of sides are congruent.
For example a rectangle could have sides of 6, 10, 6, and 10.
So the perimeter would be the sum of those sides, 6+6+10+10.
6+6+10+10 can be written like 2(6)+2(10)
For the rectangle in your question it would be 5+5+x+x, which can be written like 2(5)+2(x)
Simplify to 10+2x.
