Assuming its asking which is the easiest one to use substitution its the last one: y= 2x : x + y = 28
Step-by-step explanation:
Because y and x are already one opposite sides you can substitute y in the 2nd equation with 2x. So you'll get 3x = 28 so x = 9.333333334. Then you plug your answer for x in the original equation to get y = 18.666666667
Mr. Luna's travels east and west are irrelevant to the question. He drives 3 miles north, then he drives 4 more miles north. 3 + 4 = 7, so Mr. Luna ends up 7 miles north of his home.
