C)
you look at were the graph starts to decrease then look at the X-VALUE not the y-value
the x-val at the start of the decrease is -3 and at the end of it it is 2 therefor -3

x

2
-50 because if he owes 10 different people the same amount it would be -50 because he owes them money
Multiple 5x70 to get 350. Which makes the equation 350=5x and then you have to divide both sides by 5 to get x by itself. so 5x/5 and 350/5 makes x=70