âSome women express liquid from their urethra when they climaxâ. A second pelvic ultrasound was then performed just before the women climaxed. At the point of orgasm, the squirted fluid was collected in a bag and a final pelvic scan performed.
The base angles theorem states that if the sides of a triangle are congruent (Isosceles triangle)then the angles opposite these sides are congruent.
The angle $\alpha$ between the planes is the angle between their normal vectors, so: $$n_1 \cdot n_2 = |n_1| |n_2| \cos \alpha $$. In the following I assume that the normal vectors are normalized (their length is 1). One formula for the intersection.