Given system of equation:
y=-1/5x +1 Equation 1
y=x+4 Equation 2
Substitute value of y in equation 2.
x+4=-1/5x+1
Multiply both sides by 5.
5x+20=-x+5
Add x to both sides
6x+20=5
Subtract 20 from both sides
6x=-15
x=-15/6
x=-5/2
Now substitute value of x in equation 1.
y=-1/5 ( -5/2) +1
y=1/2+1
y=3/2
Solution is (x,y)= (-5/2 , 3/2)