Solve these using elimination.

1)
x = 5 - 9y
4x + 9y = -7

2)
3x = 5y - 9
2y = 3x + 3

3)
10x - 5 = 3y
2x - 3y = 1

4)
-6x - 4y = 10
-12x - y = 13

Apsychology student wishes to investigate differences in political opinions between business majors and political science majors at her college. she randomly selects 100 students from the 260 business majors and 100 students from the 180 political science majors. does this sampling plan result in a simple random sample? why or why not? no, because each group of 200 students in the sample does not have the same chance of being selected. yes, because each group of 200 students in the sample has the same chance of being selected. no, because each individual student does not have an equal chance of being selected. yes, because each individual student has the same chance of being selected.

Which equation can be used to measure the density of water in a spherical water tank? let w represent the number of water particles within the region.

Last week jason walked 3 1/4 miles each day for 3 days and 4 5/8 miles each day for 4 days. about how many miles did jason walk last week?