Answer:
1.64
Explanation:
Since this is a right triangle, we can use the Pythagorean theorem
a^2+b^2 = c^2 where a and b are the legs and c is the hypotenuse
6.6^2 + x^2 = 6.8^2
43.56+x^2=46.24
Subtract 43.56 from each side
x^2 = 46.24-43.56
x^2 =2.68
Take the square root of each side
sqrt(x^2) = sqrt(2.68)
x =1.637080554
To 3 significant digits
x = 1.64