[tex]a\leq b\leq c-sides\ of\ a\ triangle\ then\ a+b > c\ and\\\\if\ a^2+b^2=c^2\ then\ triangle\ is\ right\\\\if\ a^2+b^2 > c^2\ then\ triangle\ is\ acute\\\\if\ a^2+b^2 < c^2\ then\ triangle\ is\ obtuse[/tex]
[tex]a=5;\ b=7;\ c=8\\\\a^2+b^2=5^2+7^2=25+49=74\\\\c^2=8^2=64\\\\a^2+b^2 > c^2\\\\The\ triangle\ is\ acute\ (answer:B.)[/tex]
