This statement is false<span>. Because the </span>base angles<span> of an </span>isosceles triangle<span> are</span>congruent<span>, if one </span>base angle<span> is a right </span>angle<span> then both </span>base angles<span> must be right</span>angles<span>. It is impossible to have a </span>triangle<span> with two right (90^\circ)</span>angles<span>.</span>
