This is a digital matching and puzzle assembling activity on writing the standard form of the equation of a circle given its center and radius. In the first slide there are nine problems numbered with 1a,1b,1c,2a,2b,2c,3a,3b, and 3c. Students are asked to solve each problem. In the second slide the answers of the problems are given in random order. Students have to type the number of each problem next to its answer in the empty box provided. There is also a piece of a puzzle corresponding to eac