So you would first find the length of y.
To do that, use the Pythagorean's Theorem:
a²+b²=c²
in this case, c = 3, and b = 1.
a² + 1² = 3²
a² + 1 = 9
a² = 8
a = √8
Now to find z, use the Pythagorean's Theorem again:
a² + b² = c²
where √8 = a and 8 = b, and z = c.
√8² + 8² = z²
8 + 64 = z²
72 = z²
z = √72
To simplify this, take out the largest perfect square, or 36:
z = √36√2
z = 6√2
So your answer would be B.
