Susan rode her bike 30 kilometers in 2.5 hour. how fast did she ride her bike in kilometers per hour

At which value in the domain does f(x) =0?

Antonio made a scale model of a building. the model's scale is 1 inch to 235 feet and its height is 3.5 inches. what is the exact height of the actual building? enter your answer in the box.

X/y + 4y/x divided by x/y - 2y/x explain as in depth as you can how you simplfied the fractions. i don't know where to start on this : /