Sarah is riding a hot-air balloon over a lake. From an altitude of 4000 feet, she throws a rock straight down toward the water. When the rock leaves her hand, its velocity is 30 feet per second. How long will it take the rock to hit the water?

An equation where variables are used to represent known values—function notation true or false

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

Solve the equation x/4 - 5= -8 -27 -12 -7 12