Question 1114733
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If c is the longest side of a triangle and the other two sides are a and b, then<br>
(1) if {{{c^2 = a^2+b^2}}} then the triangle is a right triangle;
(2) if {{{c^2 > a^2+b^2}}} then the triangle is obtuse;
(3) if {{{c^2 < a^2+b^2}}} then the triangle is acute.<br>
For the given lengths,
{{{c^2 = 400}}}
{{{a^2+b^2 = 144+225 = 369}}}<br>
{{{c^2 > a^2+b^2}}} so the triangle is obtuse.