Here’s the easiest.. Since the distance is the same, you can take a shortcut and just average the speeds… to get

(56mph) * (3.5 hours) = 2 * (distance in miles).. solve for distance

#2 doesn’t seem to be an absolute value problem… 2x-6 = 12. Where x is the floor she lives on (which is always positive). Solve for x. I suppose you could put absolute values around the x… but that seems a little silly. Maybe there’s something I’m missing.

For #3, I’m assuming that the “model” is something that was referenced earlier in the textbook – which we wouldn’t know anything about (are you even reading these questions?)

For #4, make x equal the amount invested at 9%… y equal the amount invested at 12%… and z equal the amount invested at 10%. You can express this word problem as three equations.

y = 2x

z = x + 500

x + y + z = 1555

The goal is to reduce everything down to one variable.

Solve the first equation for x to get…. x = y/2

Now plug in y/2 into the second equation where the ‘x’ to get… z = y/2 + 500.

Now plug everything into the third equation… y/2 + y + y/2 + 500 = 1555… solve for y

Now that you’ve figured out y, you can plug that value into the other two equations to find x and z

1) Distance=3 1/2 x 48 =168 miles

2) 2x – 6 =12 so x=9. She lives on the 9th floor.

Can’t do 3 without the diagram and it’s too late to bother with 4 – sorry.