5x + 4y = 20 on a graph

Aheated piece of metal cools according to the function c(x) = (.5)x ? 7, where x is measured in hours. a device is added that aids in cooling according to the function h(x) = ? x ? 2. what will be the temperature of the metal after two hours?

Witch represents the inverse of the function f(x)=1/4x-12

What effect would doubling all the dimensions of a triangular pyramid have on the volume of the pyramid? explain your reasoning.