CAN ANYBODY PLEASE HELP ME ASAP​

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?

Ineed with this problem 21 show steps

Which equation shows y= 3 4 x− 5 2 in standard form? a 4x−3y=10 b 3x−4y=10 c 3x−4y=−10 d 4x−3y=−10