$370.80 is the right answer
.4 and .40 are indeed the same amount.
We usually drop the 0 in the 100'ths place when it is not necessary for indicating money or solving a problem with 2 decimals.
Also realize that .400 .4000 etc are all the same as well.
Answer:
the slope is 2 because when you do y2- y1/x2-x1 you get 3-(-3)/1-(-2) which is 6/3 simplified to 2
8 × 16 = 128
128 ÷ 2 = 64
64cm squared