Plz help me

Using elimination, what is -4x+2y=-12 4x+8y=-24

Atown has a population of 17000 and grows at 2.5% every year. to the nearest year, how long will it be until the population will reach 19600?

When a 757 passenger jet begins its descent to the ronald reagan national airport in washington, d. c., it is 3900 feet from the ground. its angle of descent is 6 degrees. how far must the plane fly to reach the run way? a. 37,106 ft b. 37,310.4 ft c. 23,456.6 ft d 2,492.7 ft