Find common solution for x+y=8 x=-5y

X = -5y

Substitute the value of x in first equation, 
x + y = 8
(-5y) + y = 8
-4y = 8
y = -8/4
y = -2

Now, substitute the value of y in 2nd equation, 
x = -5(-2)
x = 10

In short, Your Answer would be; (10, -2)
Hope this helps!

Ifound this on google “that means that the graph of a function with direct variation has these features: it is a straight line: because the slope is the ratio y/x = k. it passes through the origin (0,0): because y = kx = k (0) = 0.” i hope this you for what your looking for