Can you me, which equation results from adding the equations in this system? -2x+y=8 5x-y=-5 a)7x=13 b)7x=3 c)3x=3 d)3x=13

Simplify (1/2)4th power a. (1/16) b.(1/8) c.(1/4)

Acyclist bike x distance at 10 miles per hour .and returns over the same path at 8 miles per hour. what is the cyclist average rate for the round trip in miles per hour ?

Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9