In construction, the precision used to build a structure directly influences the strength of the structure. In the Rocky Mountains, many houses' roofs are built using trusses, which are strong enough to support the heavy load from snow, but light enough to build in a stockyard and transport to the construction site. Chris works in the stockyard. He has been told he needs to build a series of trusses for a new house using the pattern below. He has also been told the pattern may be inaccurate—so he needs to check and make sure the following features are all parallel, and adjust the pattern before starting. Describe the angles you would need to know to verify that line BC¯, line DE¯ and line FG¯
are all parallel to each other, and line CD¯, line EF¯, and line GH¯ are also parallel.
What could be an appropriate measure for ∠CDE? Explain your choice for that angle. Use that measure to find all other angles involved.