Marianna wants to buy a new tennis racket that cost 57.50$. she has 8$ and plans to save 4.50$ each week. how many weeks will it take her to save money?

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Solve the equation by completing the square. x^2+2x=17

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. 4x^2 + 20x + 25 = 0