# Authentic Assessment

## Bridge Construction

### Topic - Algebra - Patterns and Functions

**Task** - Constructing Bridges

Directions:

An engineer wants to know how to calculate the number of spans and supports needed for any length bridge constructed using either of the following two designs.

*Designs One: *

- Spans are yellow rods
- Supports are red rods
- This bridge design is build by adding supports and spans as pictured above to span any required length.

*Design Two: *

- Spans are black rod
- Supports are light green rod
- This bridge design is built by adding spans and supports as pictured above to span any required length.

### Conclusions:

Describe how you would calculate how many rods would be needed to build either type of bridge for any possible size. It is okay for a bridge to extend beyond the desired length by part of a span.