Answer:
Step-by-step explanation:
(I'm assuming your son hasn't learned Pythagorean theorem so I'm going to avoid using that)
10. Works because that's a rectangle or a parallelogram
11. 5,5,6,14 is possible with a weird Trapezoid
12. Works, that's a square, or a parallelogram
13. 4,3,5,14 is not possible in anyway
(Also, this math is weird, i understand how its new for you, im a tutor and struggled with this, this is what i came up with though, hope it helps)
-- Gage Millar, Algebra 2 Tutor