Solve the system of equations by the addition method.
8x- 7= -13
5x+ y= 0

Anew fountain in the shape of a hexagon will have 6 sides of equal length. on a scale drawing, the coordinates of the vertices of the fountain are: (7.5,5), (11.5,2), (7.5,−1), (2.5,−1), (−1.5,2), and (2.5,5). how long is each side of the fountain?

Ijump serves waffles, pancakes or french toast for breakfast. in addition, there are 14 syrups from which to choose. the meal comes with the choice of chocolate chips, strawberries or no topping. how many different breakfasts are possible at ijump?

In a gallup poll, 750 randomly selected adults were asked whether they are in favor of the death penalty for a person convicted of murder, and 75% of them said that they were in favor. construct and interpret a 99% confidence interval of the percentage of all adults who are in favor of this death penalty. round to 2 decimals.