some math help?

Question

1. http://i209.photobucket.com/albums/bb248/pielover757/roswell5.jpg

2. http://i209.photobucket.com/albums/bb248/pielover757/roswell6.jpg

3. http://i209.photobucket.com/albums/bb248/pielover757/roswell7.jpg

4. http://i209.photobucket.com/albums/bb248/pielover757/roswell8.jpg

Answer 1

1) Buses meet in 7 hours, so their combined speed is enough to cover the complete distance (350 miles) in 7 hours.

Since 350 mi / 7 hr = 50 mi/hr, the combined speed is 50 mph.

If one bus is traveling 35 mph, the second must be traveling (50-35) mph, which is 15 mph

2) r = 2, v = (4/3) * pi * r^3
v = (4/3) * pi * (2^3) = 32/3 * pi

That's [E] none of the above

3) [A] 5 + |x|.

A v-shaped graph around x=0, translated up a bit since the v doesn't touch the origin, suggests absolute value plus some number.

4) [A]

y^2 = 18
y = +/- sqrt(18)
y = +/- sqrt(9*2)
y = +/- sqrt(9) * sqrt(2)
y = +/- 3 * sqrt(2)

Answer 2

1. Draw a picture.
J --------350miles---------D
?mph ---->.........<--------35mph

The key here is how far did the bus leaving town D go? It was traveling for 7 hours at 35 mph right, so it went 245 miles. So how far did the other bus get?
350-245=105 so 105 miles so it went 105 miles in 7 hours
105/7=15

2. V= 4/3 * pi * r^3
V = 4/3 * pi * 8 = 32/3 pi

3. A. abs(x) +5 the abs(x) looks like a V and the plus 5 moves it up five units.

4. take sqrt of both sides add +- in front of root sign.
+- sqrt(18) = +- sqrt( 9*2) = +-3sqrt(2)