Angle measures of 45°, 45°, 90°

angle measures of 60°, 60°, 60°

side measures of 1 cm, 1 cm, 100 cm

side measures of 20 cm, 20 cm, 20 cm
which one makes a unique triangle

A3-dimensional figure has a square base and 4 lateral faces that meet at a point. explain the difference between the cross sections when a slice is made perpendicular to the base through the vertex, and when a slice is made perpendicular to the base and not through the vertex

Which of the following contains a variable?

What is the length of the segment, endpoints of which are intersections of parabolas y=x^2− 11/4 x− 7/4 and y=− 7 /8 x^2+x+ 31/8 ?