"Find the measures of two supplementary angles if their measures are 3:7 Since the ratio is 3:7 we can assume that the angles are equal to 3x and 7x?"
3x+7x=180° (180° since a line is equal to that)
then solve
10x=180
x=18
then substitute x=18 in 3x and 7x
3x=54°. 4x=126°
126° and 54°

Taking algebra two apex courses and need with these questions

What is the area of the trapezoid shown ?

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.