Lee has 3 children, the oldest is twice as old as the oungest, the middle is 5 years older than the youngest, the sum of the childrens agre is 57, how old is eaach child

Astuntman jumping off a 20-m-high building is modeled by the equation h=20-5t^2, where t is the same in seconds. a high-speed camera is ready to film him between 15m and 10m above the ground. for which interval of time should the camera film him?

The weight v of an object on venus varies directly with its weight e on earth. a person weighing 120 lb on earth would weigh 106 lb on venus. how much would a person weighing 150 lb on earth weigh on venus?

How are algebraic expressions evaluated using substitution?