T=time
d=st
r=train speed
p=plane speed
<span>160=rt
</span><span>720=pt
speed of plan is 20kmph less than 5 times speed of train
p=5r-20
we notice that 160 times 4.5=720
times first equaton by 4.5
720=4.5rt
720=pt
set equal
4.5rt=pt
divide both sides by t
4.5r=p
sub </span><span>p=5r-20 for p
4.5r=5r-20
minus 4.5r from both sides
0=0.5r-20
add 20 to both sides
20=0.5r
times 2 both sides
40=r
sub back</span><span>
p=5r-20
p=5(40)-20
p=200-20
p=180
plane is 180kmph
train is 40kmph
</span>
Amplitude is 3
Horizantal Shift 3 units to the left
Vertical Shift of 2 units up
Domain is [-1,1]
Range is [-1,5]
The shop had $2,000 in sales on Monday.
If it fell by 10% on Tuesday, then 2000 * 0.10 equals the percentage it dropped, so it dropped by $200. So they only had $1,800 in sales on Tues.
If they fell by another 20% on Wednesday, 1,800 * 0.20 equals a $360 drop. Now we're at $1,440.
The sales then increased by 25% of Monday's total # of sales. 25% of Monday's sales is 2,000 * 0.25 which equals a $500 increase. Now we're at $1,940.
Now that we're done with everything, how far are we from the beginning? That's the net change. :) We began at $2,000 on Monday, and ended with $1,940 on Thursday. 2000 - 1940 is 60, so 60 = your net change.
TLDR: Sold $2,000 on Mon, sold $1,800 on Tues, sold $1,440 on Wed, and then sold $1,940 on Thurs. The net change is $60.
