Answer:
80 units
Explanation:
triangle abc will be isosceles right triangle. angle bae and angle bce is 45° . same with triangle bcd.
take triangle aeb. angles bae and bce are 45°
sum of angles in triangle is 180
so aeb = 180 - 90=90°
6x = 90
x = 15
side = 2x-10 = 2*15 - 10 = 20
perimeter = 80units