Suppose you & your friends are going to the movies. the amount of money you spend for tickets varies directly with the number of people buying tickets. if you spend $48 for six tickets ,what is the constant of variation?

This is the equation you need to use: y = kx
So, let's put it this way:
y can be the total amount of money you spend (so $48), and x the number of people (6)

y=kx
48=k*6
k = 48/6
k = 8

The constant variation, and the price of one ticket is 8. 

Okay so for every triangle has three angles that always add up to 180 degrees. and to tell the difference between whether they are secure, right or obtuse is that acute: has one angle that is less than 90 degrees. right triangle means there is at least one angle that is exactly 90 degrees. and an obtuse angle has an angle that is bigger than 180 degrees. i’ll do #13 as an example: 13. 40 and 50 so if every triangle has 180 degrees 40+50= 90 degrees then180-90= 90 degrees so the third angle is 90 degrees and because this triangle has a 90 degree angle it means it is a right triangle