Does the following system of equations have one, none, or infinite solutions?
-4x + y = 6
-5x – y = 21

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

What is the difference between the equations of a vertical and a horizontal line?

Amanda went into the grocery business starting with five stores. after one year, she opened two more stores. after two years, she opened two more stores than the previous year. if amanda expands her grocery business following the same pattern, which of the following graphs represents the number of stores she will own over time?