Find the remaining sides of a 45°-45°-90° triangle if the longest side is 20.

45°-45°-90° is an isosceles right triangle. The longest side is hypotenuse.
All 45°-45°-90° triangles have sides that are in a unique ratio. The two legs are the exact same length, and the hypotenuse is that length times the √2.

Let a be the leg then hypotenuse = a√2.

What are the options

I’m not absolutely sure but i think it’s 7x6x5x4x3x2=5040 because as the first character you can take any of the 7 given then you are left with 5 then 6 then 4 etc.