Someone pls / what is the value of x?

The highest point on earth is the peak of mount everest if you climb to the top you would be approximately 29,035 feet above sea level at remembering that amount is 5280 feet percentage of the height of the mountain would you have to climb to reach a point 2 miles above sea level

In the xy-plane, if the parabola with equation passes through the point (-1, -1), which of the following must be true?

What adds to be the bottom number but also multiplies to be the top number with 8 on the bottom and 15 on top