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The lengths of the sides of a triangle are given. Classify each triangle as acute, right, or obtuse.A. 4, 5, 6B. 11, 12, 15

User Nikhil Katekhaye
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1 Answer

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To find out if a triangle is acute, right or obtuse we need to use the following rules:


\begin{gathered} a^2+b^2>c^2\Rightarrow acute \\ a^2+b^2=c^2\Rightarrow right\text{ } \\ a^2+b^2where c is the largest side of the triangle and a and b are the other two sides. <p>A.</p><p>In this case c=6 and we can take the other two as a=4, b=5. Then:</p>[tex]\begin{gathered} 4^2+5^2?6^2 \\ 16+25\text{?}36 \\ 41>36 \end{gathered}

Therefore triangle A is an acute triangle.

B.

In this case c=15, b=12 and a=11. Then:


\begin{gathered} 11^2+12^2?15^2 \\ 121+144\text{?}225 \\ 265>225 \end{gathered}

Therefore triangle B is an acute triangle.

User Almendar
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