When measuring a rectangular classroom, it turns out that the length is twice the width. If the length increased 40 m and the width 6 m, the area would double. Find the dimensions of the room.

In the diagram, the measure of angle 9 is 85° which angle must also measure 85°?

1. there are 25 students who started computer programming in elementary school and 25 students who started computer programming in middle school. the first group had a mean final project grade of 95% and the second group had a mean final project grade of 92%. the line plot shows the differences after 10 rerandomizations. determine whether the difference in the means of the two groups is significant based on the line plot. explain your answer.

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=