What is the axis of symmetry of the function f(x) = –(x + 9)(x – 21)?

the axis of symmetry is x =

Which of the following lines is not parallel to the graph of y = 4x +7?

The classrooms are trying to raise $1,200.00 for charity. mrs. leblanc's class has raised 50%. mr. patel's class has raised $235.14 ms. warner's class has raised 1/3 as much as mrs. leblanc's class. how much more money is needed to reach the goal of $1,200.00?

How many $20 bills do you need to have to make $280