Question 1138380
Thereis an infinite number of sets of three integers that can be the length of the sides of a right triangle.
Such sets of integers are called Pythagorean triples, and you can find lists of them by searching online for "Pythagorean triples".
Teachers like to use them in problems.
{3,4,5} is the most popular (and easiest to remember),
but {{{5,12,13}}} is also a popular one.
Here is a right triangle with such shape:
{{{drawing(300,150,-1.5,13.5,-1,6.5,
triangle(0,0,0,5,12,0),
rectangle(0,0,0.5,0.5),locate(-0.4,0,A),
locate(-0.4,5.7,C),locate(12.1,0,B),
locate(5.7,0,c),locate(-0.5,3,b),
locate(6,3.2,a)
)}}} {{{tan(B)=5/12}}} , so {{{tan^"-1"(5/12)=B}}} , and {{{cos(B)=5/13}}} ,
so {{{sec(B)}}}{{{"="}}}{{{1/cos(B)}}}{{{"="}}}{{{(5/12)^"-1"}}}{{{"="}}}{{{highlight(12/5=2.4)}}}