The solution set of the equation 3x2+x = 9 is

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics

What does independent variable and dependent variable mean in math?

Math i have no idea how to do a and b