Can someone explain how to factor 8x + 20?

For which rational expression is -2 an excluded value of x?

The data in the table represent the height of an object over time. which model best represents the data? height of an object time (seconds) height (feet) 05 1 50 2 70 3 48 quadratic, because the height of the object increases or decreases with a multiplicative rate of change quadratic, because the height increases and then decreases exponential, because the height of the object increases or decreases with a multiplicative rate of change exponential, because the height increases and then decreases

How do i do this? i don’t understand