To find the hypotenuse of a right triangle, you can use the pythagorean theorem, which states that a² + b² = c², with a and b being your two legs and c being your hypotenuse. So since we are given a and b, we can conclude that 6² + 6² = c². This means 72 = c². To find c you can do the square root of 72, which means c = √72, or as a decimal approximately 8.5 rounded to the nearest tenth. Hope this helps. :D. Feel free to ask more questions or question my explanation.
