Y=2x-4
y=x-1 what’s the answer to this how do u solve it

How do you solve a question like this?

For a school science project, john noted the temperature at the same time every day for one week. the high temperature for the week was 27°f, and the low temperature for the week was −3°f. what is the difference between the high and low temperatures john recorded?

Theo found the driving distance from glacier national park to yellowstone park to be 448 miles. theo used a map that had a ratio of 5cm/300mi. how many centimeters is the distance on the map? round to the nearest unit if necessary. 4 centimeters 7 centimeters 64 centimeters 90 centimeters