Find the lengths of the missing sides

Eric drew a scale drawing of a country park. the scale he used was 1 inch = 2.5 yards. the picnic area is 80 yards wide in real life. how wide is the picnic area in the drawing ?

X+y=-4 x-y=2 use elimination with adding and subtraction

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?