Felicia, a parent:

A rectangle whose base is twice its altitude is inscribed in a circle whose radius is 5 mm. Find the area of the rectangle.

Hi Felica, In my diagram I let a mm be the altitude of the rectangle. What is the length of the base? Angle CAB is a right angle. What is the length of AB? What is the length of CA? What does Pythagoras theorem say for triangle CAB?

Solve for a.

Penny