Theorem: If two<span> angles of a </span>triangle<span> are not </span>congruent<span>, </span>then<span> the </span>sides<span> opposite them are not </span>congruent<span>, and the longer </span>side<span> is opposite the larger angle. </span>Two<span> ways to prove that a </span>triangle<span> is isosceles </span>If<span> at least </span>two sides of a triangle are congruent,then<span> the </span>triangle<span> is isosceles</span>
