For both questions, look for congruent triangles. Once you've identified the congruent triangles, study the angles.
Hello, djo4567!
I'll do the first one.
Connect the midpoint of the sides of a rhombus.
Prove that the midpoints form a rectangle.
Code:E A o * * * o * * * o B * * * * * * * * * * * * H o o F * * * * * * * * * * * * D o * * * o * * * o C G
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