This equation leads to x being an imaginary number based on what you gave. However if you meant x+y ----- = 1 & 3x-7y=2 ..2 Then, x+y=2...(1)x7 3x-7y=2...(2)x1
--> 7x + 7y = 14...(3) ......3x - 7y = 2....(4) --> 10x=16 --> x=16/10 --> x=8/5 or 1.6 Put x=8/5 in (1) (8/5)+y=2
It is C, if it falls 14 ft. and it travels back up 7 ft. and then falls another 7 ft, and stops at the ground now you add it all up 14+7+7=28. hope that helps you.