The perimeter is equal to the sum of the measures of the sides.
we know 3 sides. to find the diagonal missing side:
The trapezoid is formed by a square and a right triangle with sides
a=4 and b=3
Apply Pythagorean theorem:
c^2 = a^2+b^2
Where c is the hypotenuse of the triangle, and a and b are the other 2 legs.
Solve for c:
c^2 = 4^2+3^2
c^2 = 16+9
c^2 = 25
c=√25
c= 5
Add all the side lengths:
Perimeter: 4+4+7+5 = 20