In an isosceles right triangle the hypotenuse is 8.4 in find the length of a side to the nearest tenth of an inch

In an isosceles right triangle, the two legs will be equal to each other.  We can use the Pythagorean Theorem as follows:
a² + a² = 8.4²  where 'a' is the length of the two equal legs
2a² = 70.56


a = 5.9 to the nearest tenth of an inch.