Answer:
x = 8
Step-by-step explanation:
add all side lengths to find the perimeter
5x + 6x + 5 + 6x +3 = 144 add like terms
17x + 8 = 144 subtract 8 from both sides
17x = 136 divide both sides by 17
x = 8 to find the side lenghts replace x with 8 in each expression
