You are doing chores to earn your allowance. for each chore you do, you earn $3. in the equation below, c is the number of chores you do, and d is the number of dollars you earn. the relationship between these two variables can be expressed by the following equation: d=3c identify the dependent and independent variables.

How do you use the elimination method for this question? explain, because i really want to understand!

What is the value of x in the this question ?

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters