The 1 question is 3 and the second one is 3
Answer:
A = 744 meters B = 489 meters
Step-by-step explanation:
A = B + 255
2B - A = 234
-2B -2B Subract the -2B from both sides
-A = -2B + 234
A = 2B - 234 Divide by -1 to get A alone
B + 255 = 2B - 234 Set both equations equal to each other
- B -B
255 = B - 234
+234 +234
489 = B
Plug 234 in for B in the original equations
A = 489 + 255
A = 744
Consider for a moment building a tree with all possible choices. The first row would contain 8 books (each possible choice for the first book). Then, the second row would contain 7 books for each book in the first row (the choices possible for the second book). Otherwise, it would be 8*7. Following this principal, we continue to multiply down to 1. 8*7*6*5*4*3*2*1. This is also known as 8!, a factorial.
Finally, 8! = 40,320
