Solution to @kriblo's equal area puzzle: https://scratch.mit.edu/projects/841244227 One right angled triangle. Each side of the triangle is a diameter of one of the circles. The shaded region R is the region inside the two smaller circles but outside the largest circle. In the project, I prove that the area of R is equal to the area of the triangle. I have also made a project in Desmos that uses the Law of Cosines to show that the area of the triangle is always equal to the area of the shaded region: https://www.desmos.com/calculator/k9ysaovvt5. In the Desmos, you can move the purple dot to change the height and width of the triangle. The value of the variables T (area of the triangle) and R (region inside the two smaller circles but outside the largest circle) should be equal to each other wherever you move the purple dot. -- Credits @RokCoder and @kriblo_test for sharing the puzzle @asnow2021 for the scroll bar
