Danielle and drew are sightseeing for the day. between the two of them they take 77 pictures. danielle takes 17 more than twice as many pictures as drew.

part a. how many pictures does drew take?

part b. how many pictures does danielle take?

Let's break this down:
Total Pictures = 77
Drew's Pictures = X (An unknown amount)
Danielle's Pictures = 17 + 2X (2 times the amount of Drew plus 17)

So, let's put the pieces together, the problem should look like this:
   Total Pictures = Drew's Pictures + Danielle's Pictures

So let's put in what we know:
   77 = X + (17 + 2X)

1st step is to get X to one side:
   77 = X + 17 + 2X
   -17       - 17
=> 60 = X + 2X
=> 60 = 3X

Now that X is on one side, the 2nd step is to get X to be alone:
   60/3 = 3X/3  (We have to divide to each side because the answer is equal)
   20 = X

So, now that we know what X equals, let's go back to what we broke down:
Drew's Pictures = X (An unknown amount)
Danielle's Pictures = 17 + 2X (2 times the amount of Drew plus 17)

*Remember that X = 20*
So the amount of Drew's Pictures (since the amount is equal to X) is 20.

Danielle had 17 + 2X pictures which means:
17 + 2(20)
17 + 40
57

So Danielle took 57 pictures