Question 521455
5x+y=20 (1)
5x+5y=15 (2)

(2)-(1):
4y=-5 => y=-5/4

from (1):

x=(20-y)/5 = (20+5/4)/5 = 17/4 = 4 1/4


Ans:
X= 4 1/4
Y= -(1 1/4)