The side of a rhombus is 8cm long. One of its diagonals is 13cm. How long is the other diagonal?
AAAaannndd the bot gets it wrong yet again!
the diagonals of a rhombus are perpendicular, so in this case they form four congruent triangles, with sides 13/2, √87/2 , and 8
so the other diagonal has length √87