IM 7.7.4 Practice: Solving for Unknown Angles

 is a point on line segment .  is a line segment. Select all the equations that represent the relationship between the measures of the angles in the figure.

Which equation represents the relationship between the angles in the figure?

Segments  and intersect at point , and angle  is a right angle. Find the value of .

Select all the expressions that are the result of decreasing  by 80%.

Andre is solving the equation . He says, “I can subtract  from each side to get  and then divide by 4 to get ". Kiran says, “I think you made a mistake.” How can Kiran know for sure that Andre’s solution is incorrect?

Describe Andre’s error and explain how to correct his work.

A train travels at a constant speed for a long distance. Write the two constants of proportionality for the relationship between distance traveled and elapsed time. Explain what each of them means.