Pls help my child has no clue and this math is too hard for me to understand!!

How do i do this using elimination 2x+3y=12 x-y=6

What is the point slope form of a line with slope -5 that contains point (2,-1)

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables