Answer
c=13
Work Step by Step
Given that triangle is right angle triangle where a=12 and b=5
and c has to be found
formula for finding hypoteneus of right andle triangle is $a^{2}$+$b^{2}$=$c^{2}$
so after putting values of a and b,
$12^{2}$+$5^{2}$=$c^{2}$
144+25=$c^{2}$
$c^{2}$=169
$\sqrt c$=13