Triangle STU is congruent to triangle UTX is the missing step. AAS (angle-angle-side) is a method of proving 2 triangles congruent, and using the already proved information, you can find the triangles that are congruent by AAS.
The answer will be 2^10 or 1024 cells
Happy birthday, and the answer would be 3m(squared). The formula is LxH/2.
