Answer:
x = 12
Step-by-step explanation:
You must use the Pythagorean Theorem to solve.
Since a^2 + b^2 = c^2 in right triangles, you must find the value of a that will make c and b appear true.
You have already:
a^2 + 5^2 = 13^2
a^2 + 25 = 169
a^2 = 144
The only number that when squared is 144, is 12.
x = 12
