Question 498899
{{{7^2}}} +{{{b^2}}}  = {{{10^2}}}
49 +{{{ b^2}}} = 100
{{{b^2}}} = 51
b = {{{sqrt(51)}}}
{{{7^2}}} + {{{7.14^2)}}} = 100
49 + 50.98 = approx 100.
This does check. 
Cleomenius.