So if y = -8x and y-8 = -x then you can sub y with -8x in the second one. So that will make -8x-8=-x which can be simplified to -7x - 8=0 then again to -7x = 8 so -x= 7/8 so x = -7/8. Sub that into y-8=-x making y-8= 7/8 so y= 7/8 +8 = 71/8
Soooo point = (-7/8, 71/8) hope this helps (=・ω・=)
Edit:attached a pic cos I'm a nerd. 2 reply