The first european settlements along the coast of sub‑saharan africa included st. louis, luanda, and lourenço marques (now maputo). from what country did the settlers come?

Portugal

Explanation:

The earliest European settlements along the coast of Sub-Saharan Africa Settlers and explorers where from Portugal for the exploration of oceanic routes and island groups around Africa. The 15th century marks the age and exploration of Sub Saharan Africa, under Henry the Navigator who went to St. Louis, Sunanda, and Lourenco, etc. After which came the Dutch to colonize Africa. The cape code remained under the dutch rule till 1803, after which the Britishers took over from 1806. All these came from European countries and tried to settle in Africa as it was wide and full of resources.

I'm pretty sure there's a geometry rule for   anyways, if the triangle is equilateral, and the circle is circumscribed, the circle is outside of the triangle.  to find the area, you need the radius.  the radius should be a straight line from the center of the triangle to any of it's points.  draw lines from the center of the circle to each of the triangle points.  draw three more lines from the center to the middle of the sides of the triangle.  you should now have six separate 30-60-90 triangles inside of your original triangle. use your 30-60-90 rules to solve for the radius, then the circumference.