B. x=5*sqrt3
you can solve this by using :
a^2+b^2=c^2
Remember that you can only use this equation for right triangles & the longest side will always be c !!
so plug in what is given to you.
a^2+11^2=14^2
simplify.
a^2+121=196
our goal now is to get a(x) by itself.
subtract 121 on both sides.
a^2=75
again, we want a(x) by itself.
square root both sides.
a=8.6602
5*sqrt3 = 8.6602
Hope this helps!! :)