Step-by-step explanation:
Well in general, we can represent subtraction as: 
"z" represents the difference, and it really just represents x with y taken away. So if we were to "give back" this y value, we should get "x".
This means that: 
So one way to check, is adding the value that's being subtracted (y value) and the difference (z value), this should get you the value that is being subtracted from (x value). If you don't get the original value that's being subtracted from (x-value) then you know the answer you got is wrong.
Y=140 because U have to go 35 divided by 2 and 8 times 17.5
Im gonna guess 6.00 beacause it says round to hundreths
Answer:
b=-5
Step-by-step explanation:
Divide by -9 to eliminate the -9 on -9b
(Since -9b is the same thing as -9 times b we can use the inverse of multiplication which is division to eliminate the -9 from b but we need to do it on both sides to make it balance)
-9b/-9=45/-9
b=-5