So Jocelyn we shall solve this like
-1+x-x=x-8+(-x)
( first step would be subtracting the x's in the first expression which gives a zero so we wouldnt write it)
-1=x-8+(-x)
(now we will take our -8 to the other side and change it to 8 as when bringing a variable or a number to other side we change its sign)
-1+8=x+(-x)
( now we will subtract them both and see what we get)
7=0
so sorry this question isnt correct or i dont know , maybe i didnt solve it properly but i checked in the calculator on the hme page and it doesnt give a proper answer so i guess theres a problem in the question!
+11912 
