Please solve V=P+ma for m

How do i do this activity, is appreciated

Television sizes are based on the length of the diagonal of the television's rectangular screen. so, for example, a 70-inch television is a television having a diagonal screen length of 70 inches. if a 70 inch television's diagonal forms a 29°angle with the base of the screen, what is the vertical height (1) of the screen to the nearest inch? 70 inhin

Which graph represents the linear function below? y-4= (4/3)(x-2)