Answer:
3.6 m
Step-by-step explanation:
Because the triangle is a right triangle, we can use the pythagorean theorem:
a^2 + b^2 = c^2 (a and b are the legs of the right triangle, and c is the hypotenuse)
6^2 + b^2 = 7^2
36 + b^2 = 49
b^2 = 13
b = 3.6 m