Amir stands on a balcony and throws a ball The balls heigh:x
is modeled by
h(x)=-(x+1)(x-7).
How many seconds after being thrown will ball reach its max height.

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.