Answer:
x=16
Step-by-step explanation:
use the Pythagorean theorem.
[tex]\sqrt{a^{2}+b^2 \[/tex]= [tex]c^{2}[/tex] Another way, you can do the problem is that you can see
[tex]\sqrt{12^2+b^2[/tex]= [tex]20^{2}[/tex] that 12 divided by 4 is 3 and 20 divided by 4 is 5, which is
144+b^2=400 the two numbers from the special 3,4,5 triangle, and since
-144 -144 you have figured that much out, you can multiply 4*4 and
------------------------ get 16.
b^2=256
[tex]\sqrt{256\\}[/tex] = 16