Maths 3D Trig Help? (1 Viewer)

[bongoli]

A,B,C and D are four points, equally spaced on the circumference of a horizontal circle of radius length 3cm. P is a point above the circle such that PA = PD = 4cm and PB = PC = 6cm. Calculate the size of angle APC.

Thank you!

 

[braintic]

A,B,C and D are four points, equally spaced on the circumference of a horizontal circle of radius length 3cm. P is a point above the circle such that PA = PD = 4cm and PB = PC = 6cm. Calculate the size of angle APC.

Thank you!

There is actually very little to visualize here in a 3-dimensional sense.

APC is a triangle (not vertical, but who cares).

You know the lengths of the three sides of this triangle:
PA = 4
PC = 6
AC = 6 (the diameter of the circle, since the points are equally spaced around the circle)

Angle APC is an angle of this triangle, so you should be able to find it by using the cosine rule in this triangle.