Short Answer: x = 2*sqrt(2)
The Pythagorean Theorem states that
a^2 + b^2 = c^2
Givens
a = 2
b = 2
c = ???
Sub and solve
2^2 + 2^2 = c^2
c^2 = 4 + 4
c^2 = 8 Take the sqrt of both sides of the equation
sqrt(c^2) = sqrt(8) Express 8 in it's prime factor form.
sqrt(c^2) = sqrt(2 * 2 * 2)
The rule about square roots is
If you have a pair of prime factors under the root sign, you take out one of the prime factors and throw the other one away.
sqrt(c^2) = 2*sqr(2)
Answer x = 2*sqrt(2)