William can create a design using as many pattern blocks as he would like. One triangle equals 1. He decides to build a design using four pattern blocks and the total is 16. How many triangles did he use in his design? 1. Use pattern blocks to create the design William made. 2. Tap the add button. 3. Take a photo of the design. 4. Use the drawing tools and mic to explain how you solved the problem. 5. Tap the check to add to your portfolio.