Please Help!

[Dakota120]

I have two questions that I need some help on. I'll write the questions and then write how far I got in each one.

1. Find q in terms of a, b, and p if the line passing through (a, b) and (p, q) has slope ap / b

a. Show how you got your answer
b. prove using an example


2. Carla is traveling to Pittsburgh, which is 311 miles away. She drives at a fixed rate for the first 2 hours. She increases her speed by 7 miles per hour for the next 3 hours. What are the rates of speed for each part of Carla's trip.


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For number 1 I plugged the numbers into the slope formula and I got:

q-b / p-a = ap / b

Now I am lost and have no clue what to do, cross multiple?

Thanks for any help!!!!

 

[Daniel_Feldman]

You have:

q-b / p-a = ap / b


So now we just need to solve for q. we need to take everything else to the other side. If we multiply both sides by (p-a), we get


q-b=((p-a)(ap))/b

So q=b+((p-a)(ap))/b


You can leave it like that, or make it into one fraction-your choice.




I'm not understanding problem two: Does she complete her trip in those 5 hours? Also, what does "rate of speed" mean?

 

[stapel]

2. Carla is traveling to Pittsburgh, which is 311 miles away. She drives at a fixed rate for the first 2 hours. She increases her speed by 7 miles per hour for the next 3 hours. What are the rates of speed for each part of Carla's trip.

Use the uniform-rate equation, "d = rt".

. . . . .first bit:
. . . . .rate: r
. . . . .time: 2
. . . . .distance: 2r

. . . . .second bit:
. . . . .rate: r + 7
. . . . .time: 3
. . . . .distance: ...?

Complete the table. Add the two "distance" expressions, and set equal to the given total distance. Solve for the variable.

Eliz.